Rooftop Wind Turbines Ready For Commercial Use

Note: Images and Video © Lucid Dream Productions

Wind turbines designed to be installed on rooftops are generating a lot interest lately. These compact turbines can be located on top of buildings, or attached to other parts of large structures like bridges. In turns out, though, that installing wind turbine in a city environment is a bit of an art. That’s because each building has it’s own unique wind footprint, and nearby buildings also tend to generate strange wind patterns. So placing the wind turbines in the right place is key. The other challenge is to make these turbine noise-free and visually unobtrusive.


For many years, a fellow named Bil Becker has been hard at work developing his Aerotecture turbines. The turbines are elegant devices which incorporate both Savonius and Darrieus styles into one turbine (pictured here). His company has been installing these turbines in a few test locations around Chicago like the Near North Apartments at the Mercy Lakefront Housing.


This installation features eight Aeroturbines mounted horizontally to the roof of this 96-unit housing development. The building, designed by Murphy/Jahn Architects, is a fine example of building-integrated wind energy technology. The geometry and orientation of the building was designed specifically to increase the speed of the wind as it flows over the roof.

Here’s a video clip about the turbines:

So how power do these turbines produce? The Aerotecture FAQ says: “The estimated rated output of the 510V is 1kW in 30 mph winds; the estimated rating for the 520H is 1.8kW.” As for the price:

The 510V Aeroturbine has an estimated cost of $15,000; the 520H Aeroturbine has an estimated cost of $21,000. This price includes the full system: rotors, cages, all the custom mounting structures, and electronic equipment (batteries are optional and sold separately). The cost of Aeroturbines will dramatically decrease with the advent of mass production.


If you are interested in a wind turbine for you home, you might want to consider a Sunforce. There are also some books about wind turbines available.

Link: Aerotecture

See also this article by Chicago Conscious Choice on Bil Becker and Aerotecture.

Comments 88

  1. Web site is not yet ready. Iam very much interested about wind mill+ solra energy ( Hibird) for domestic purpose.We had a trading estabilishment. please mail your products details, conditions for dealership, price list etc

  2. I seriously doubt this stuff works. It is amazing that so much money is being spent. I should like to see 1 ‘real’ installation (and there are many with this machine now) that would disclose actual energy produced per year, or month or whatever. I believe this is a scam. Worst yet – tax dollars are being spent on many of these installations. Wind does work. It has to be used where there is a wind resource however (and that does not exist in urban situations). The machines need to be on tall towers located in windy places to even come close to making their energy cost effective. In my opinion, this aerotecture stuff is going to give the industry a black eye… worse than it already has. I could be wrong – I’d just say prove it. I want to hear from an ‘aerotecture customer’ about their average energy production from the *wind turbine* (not the wind turbine combined with solar panels). GRRRR……

  3. Super idea this would sell very well in Ireland, I am interested in marketing this product here, after all we are the wind capital of the world.
    Jim O Neill

  4. Hello,
    I am a local contractor/alternate energy company here in northern IL. I am currently seeking a rooftop product for my clients. I like your product. I am interested in seeing more. Being local, is there a way to set up a meeting with yourself and my business partners in order to learn more about your product in depth. Becoming an installer/dealer? We would like to see your product in person and get more familiar with it to be able to make the decision if it is right for our clients. We have a very large commercial building client base here in Chicago.

  5. Hello,
    am Prabu from India.. am doing project about , “wind turbine to built in home” and make to commerical purpose. So please send the details about small wind turbine and their types and control methods.

    My mail id is kdasaprabhu@gmail.com

  6. Hello

    I’ve already reached there about 2 years. I am interested in your technology.
    to sell your product in French Polynesia, I would like to know the conditions of franchise, in the hope of a positive response, I am at your disposal.

    GSM: +689 773773

  7. This so-called Baker Turbine is a scam. The device has never been tested, but along with a few friends we tested (theoretically) the concept. It doesn’t work.

    This is why Mr. Baker has never attached the turbine to a generator. He is trying to raise money with false hope. DOE has already dismissed this guy as a phony.

    It is a shame to see this scam published all over the internet. It gives inventors a bad name.

    1. Scott Johnson said: “This so-called Baker Turbine is a scam. The device has never been tested, but along with a few friends we tested (theoretically) the concept. It doesn’t work”
      “It is a shame to see this scam published all over the internet. It gives inventors a bad name.”
      Mr. Johnson: As the inventor of concept and the builder of concept into a model that proves the concept; I can only conclude that you are an idiot who is unable to understand the Science of Low Pressure Turbine Dynamics. How dare you discredit me because of your ignorance?
      It is true the DOE refuses to officially test my turbine. And why is that? The answer is that the dynamic out modes the propeller driven wind mill and they and their partners do not want the new technology exposed because the multinational corporations would not be able to control it.
      For this very reason this technology is free to everyone. No one will ever own and control the technology because as the originator of concept and builder of proof of concept; I declare the technology is free to everyone. Any machine shop can duplicate and produce the technology with my blessing.
      I know that is to much for your pee brain, but I am more interested in Science and the advancement in Science then making money. I have a very distinct dislike for Vulture Capitalist and their elk and refuse to even talk to such base persons. I have too many other Science and political projects going on that are way over your limited ability to understand.
      Look at the facts and proof before you, idiot, before you slander someone else.
      My job as an inventor of originating concept and building a model to prove the concept is done. The turbine dynamic stands in Science in spite of your ignorance.
      Two videos:
      Description of how the Low Pressure Turbine Dynamic works:

  8. Please send me all information on your wind turbines. Our firm installs cable TV services and is very interested in becoming a distributor, reseller, or installer of your turbines here in the great mid west. We already have a number of sales leads, and would like very much to see your wind turbines positively impact our customers bottom lines. Thanks in advance for your cooperation, A. Ferguson VP ReadyCom, Inc.

  9. These are pretty neat but very experimental. That design has no accomodation for winds that are at whatever direction they will be blowing. I would not buy anything that’s this experimental before looking at proven working systems. Have a look at WindEnergy7.Com site and all their video footage of actual turbines, inexpensive enough to put on your home, certified to 130 mph. Rooftop Wind Turbine The systems that are pictured and video at that site are patented rooftop wind turbines that are working on homes and businesses all over the US, available and shipping now. Have a look.

  10. I didn’t know these turbines actually spin. At all the test areas they just sit there. Wind at 5/ms or otherwise. Maybe its best we do our research before we buy one.

  11. I’m looking for the name of the manufacturer of a rooftop wind turbine. It’s a long rotor with a narrow diameter, and runs along the peak of the roof the entire length of the roof peak. I believe it’s actually in the attic below the roof peak , and vented.


  12. I am very fasinated with the tectnolgy of how you can use the wind for energy and save the planet. Do you have any plans , books or kits you sell to the average home owner. I would love to enquire more on this product. With the price of goverment control energy cost rising quite often , it,s getting harder for the average home owner . We have to start somewhere, so any information or links would be appericated .

  13. Dear Sirs: My name is Jim ,I own Encore Development co. in Sacramento Ca. I am Planning to build a 26,000sq ft Performing Arts center with classrooms and a 500 seat theater, in a rural 20 acre “park like” setting A childrens Art and Education Center. I have long planned to be inovative with concept and design,fused with alternative energy and sustainable resources. I believe greatly in your product ,and wouid love to incorrperate it’s use and demostrate its value to the growing community of Elk Grove Ca .I hope it will provide efficeint amount of energy to be of a added value for a selling point with city officials and surrounding land owners/citizens to place this project on rural land 2000ft from subdivisions 1800 stuudent high school/middle school, and a church on 3 acres. Thanks Jim L. Brown

  14. The Baker Wind Turbine is a major breakthrough in wind energy technology. The super quiet, Low Pressure Turbine is enclosed and 100% bird and people safe which allows the turbine to be installed and operated in close proximity to people. This eliminates the need for long transmission lines because the electricity is consumed close to where the electricity is generated. The 12 feet in diameter Model #3 Baker Wind Turbine is mounted on a car trailer and the unit is easily transported. Set-up is easy. The outriggers lift the turbine foundation and stabilize the turbine so that it can rotate 360 degrees. The finders and tires are removed. No tower is needed; all that is necessary is a 6’ by 6’ wind flow. More efficient and powerful than a single dimension propeller driven windmill, this multidimensional wind energy turbine dynamic has never been seen before. Of course, the multidimensional turbine dynamic does not even resemble a single dimension propeller driven windmill. Google Baker Wind Turbine and two videos will appear; the longer video demonstrates the Low Pressure Turbine Dynamic.
    Let me explain to you the basic turnaround in wind energy science and technology demonstrated by the Baker Wind Turbine. You don’t have to be a genius to understand wind energy.
    First, the maximum amount of energy in the wind is directly in front of the wind. This is the basic and simple premise and is easily proven to anyone logically. (Aristotelian logic is the foundation of all science.) While standing in the wind, face the full force of the wind which is directly in front of the wind. Now, form both hands into a cup which represents a ½ round, cupped turbine vane with volume. Now, cross over your hands and form a blade with no volume representing a propeller driven wind mill. Which of the two forms catch more wind and has full thrust from the wind?
    The first part of the equation is solved: The maximum amount of energy in the wind is directly in front of the wind and the best surface form to catch the wind and consequently has more thrust and power is a ½ round aluminum turbine vane with volume.
    The second part of the equation is as logical. Which direction will the maximum wind catch area turbine vane turn? Naturally, the turbine vanes and rotor turn harmoniously in the same direction as the wind is blowing. This eliminates wind noise caused by turbulence. A propeller blade rotates sideways to the wind energy airstream which results in less power produced, noise from propeller turbulence and high stress on bearings and blades creating high maintenance cost. Propellers are so big; birds can’t see them and they have devastated wild bird populations. Check out the out of control wind propeller explosions on You Tube.
    The third part of the equation is that the more cupped wind catch surface area that is directly in front of the wind, the more powerful the turbine. A single dimension propeller can only expand in size and power by increasing its’ diameter. The multidimensional Baker Wind Turbine can not only increase its’ power by increasing its’ diameter but can expand horizontally and add exponentially more wind catch surface area and power.
    The Baker Wind Turbine has 144 cupped turbine vanes that are 3 inches wide (5 ½ inches of surface area). The 3 inch aluminum vanes give us 11 inches of weld at the cupped base. Each turbine vane has 1 1/2 sq. ft. of cupped surface area. This is important because the stress per catch area unit is low as apposed to a large catch area with a high stress attachment to the hub. No one turbine vane pulls by itself but pulls together with the other turbine vanes in a “gang”. This spreading of wind energy over the rotor maximizes the wind catch area and spins the rotor smoothly without vibration. Each turbine hub has 6 turbine vanes that are 6 ft. long. There are 24 hubs (6ft. wide) and there are 18 rows. Each row contains 48 lineal ft. of turbine vanes. At any given moment, the top section contains 108 sq. ft. of cupped wind catch surface area. As each row is assembled, they are progressively stepped which forms a horizontal twist. Twist is torque and torque is horsepower. The more twist, the more horsepower. Dividing the diameter into 18 lateral rows creates massive torque that is visible. For example take a wood screw and hold it sideways and turn it. You will notice that the screw is made up of one helix and 8 or more twists (or flights). The Baker Wind Turbine is Like the Archimedean screw but made up of 6 helixes with 8 twists which torque from right to left six feet. The overall dynamic of the Baker Wind Turbine is germane to High Pressure Turbine Dynamics but adapted to Low Pressure Turbine Dynamics which I am the inventor of and the Baker Wind Turbine is the test prototype. Just as Mr. Parsons’ invention of the high pressure steam turbine revolutionized steam power; the Baker Wind Turbine will revolutionize low pressure wind power.
    The Baker Wind Turbine rotor has a lower surface to weight ratio than a propeller windmill so the rotor and shaft which weigh 660 lbs. begins turning on 1 or 2 miles an hour of wind and will operate smoothly and quietly in a 100 mile and hour wind at an estimated (920 R.P.M). High pressure steam and gas turbines operate at 20,000 to 50,000 R.P.M or higher; so in high winds the low pressure turbine dynamic is figuratively just loafing along. The Baker Wind Turbine not only has a wider range of operation but also produces more energy at any given wind speed than a propeller driven wind mill and therefore the new turbine wind energy technology should rightfully outmode the old propeller driven windmill technology. The Baker Wind Turbine, like all major inventions, has a wide range of applications that will change roof top architecture, bridge design, ship design, high speed (forced air) train electric grid locomotives, forced air/ electric cars, parks, airports and all areas where the wind can be utilized in a natural or forced air environment. The turbine is enclosed so the housing can be easily painted to blend in with the surrounding area.
    The last part of the equation is a little harder to grasp, even some engineers don’t get it straight. Those who defy convention and who can think individually in multidimensional terms get it right away.
    First the single dimension. One assumption in Betz’ Law is that a solid wall is considered 100 % efficient in the wind and a propeller is considered 50% efficient because half of the wind flows through the propeller which causes the propeller to turn. So, 6 feet by 6 feet swath of airstream at, lets say, 10 pounds pressure per square foot (pounds is air speed and density) would give you 360 pounds of pressure thrust overall. A 50% efficient propeller would have 180 lbs. of thrust available. A three blade propeller with 5 ½ inch wide blades and 6 foot in diameter (4 1/2 sq. ft. surface area or 40.5 lbs thrust) produces but a fraction of one horsepower. The reason for this is a small surface area propeller rotates on a flat plane sideways to the energy source, has little torque, and is of a single dimension.
    The multidimensional Baker Wind Turbine wind in-take is 6 feet high by 6 feet wide by 12 feet deep. The wind travels laterally across the turbine top section 12 feet to the other side which creates rotary power. The turbine rotor vanes are denser close to the center of the hub and wider at the tips and spaced such that the wind passes through the turbine to the other side. Again, hold up the wood screw. Notice by looking across the top half of the screw that there are air passages to the other side? Remember the Baker Wind Turbine has 6 helixes and 8 twists and the air passages move from right to left six feet? Now, look at the down wind side of the screw and you will notice that the flight is open and fanned out and is not drafted by the spiral? The turbine spirals leading edge is made up of many turbine vanes from many different rows so they do not draft one another. Of course, the leading edge of the opening is constantly changing as the rotor turns. At the apex of the turbine, as observed directly in front of the wind in-feed, the vanes form a continuous wall dimensionally. Because there are dimensional openings between the turbine vanes, and air is highly fluid, the wind powers all nine rows at any given moment from one side to the other. Each row is one dimension under wind power and there are 9 rows. There are 48 lineal feet of 3 inch cupped turbine vanes per row and 108 cupped sq. ft. total under power. If we figure out our total surface area in the top section it would contain 198 sq. ft. of surface area under wind power. At 10 pounds per sq. ft. that would be 1,980 pounds of thrust overall. That is 49 times more than the estimated efficiency of 40.5 pounds thrust for a single dimension propeller operated in the same 6 foot by 6 foot airstream! The Baker Wind Turbine is even more powerful than just converting speed and density of air into rotary power, the traveling torque creates even more horsepower, however, digging into traveling torque equations at this time is not necessary. My point has already been proven in science that Baker Low Pressure Turbine Dynamics is at least 49 times more powerful then a propeller driven wind mill dynamic and my 12 feet in diameter low pressure turbine proves it. That is why I built model #3 so that people could see the powerful turbine dynamic operate even though they do not understand how it works or all of the ramifications of it working. Now you know how it works and basically the breakthrough technology of Baker Low Pressure Turbine Dynamics. Did you get it? Or was it to much for your wee mind? For those who get it, read on. For those who don’t get it; drive down the road at 65 mph. and cup your hand into the wind and let it jerk your arm back and each time ask yourself “where is the power and energy”?
    The reason the modern American Green Energy Economy is not moving forward is because independent scientist and individual inventors, like me, are without funding. The reason there is no funding is because the economic powers that be, the status quo, has snuffed any State or Federal funding programs for independent green energy inventors. Are you surprised there is no level ground? Do you know what scares the hell out of the multinational Big Oil and energy barons? The answer is the advancement of science with new inventions that they can’t control (their economy) that would outmode the use of fossil fuels for energy (their product). That is the cause of man made Global Warming.
    Logically, one would think that the first government action would be to utilize our national talent by holding a national green energy science contest thereby acting free from Big Oil. I am not the only independent inventor; there would be thousands of qualified applicants with new concepts. The winner would receive a one million dollar reward to further develop the new green energy concept. Ten million a month could finance and develop ten new grass root industries employing thousands in green energy jobs. Out with the old and in with the new, let the best win in science and the lesser fold or be outmoded by something even better. That is fair competition and free enterprise. A modern American Main Street Capitalism based on a green energy economy would grow from the bottom up and not be dominated and controlled by multinational corporations from the top down. Great inventors were individuals not controlled universities; they are the ones who should be funded.
    Lawrence Baker
    650-218-9434 windcatch@gmail.com

  15. If I wanted to use one of these images, is there someone I can contact or do I just write “(c) Lucid Dream Productions”?



  17. I am living in Chicago, can i have an opportunity to visit your company? i am very interested in selling this product in China, looking forward to your reply.

  18. I am very much interested in wind energy and please send me the details of your products

  19. My father is a retired mechanical engineer living in the SC foothills. He’s on the local electrical co-op board. Living on the top of a granite hilltop definately provides more than the usually 1 or 2 rated winds for standard wind generators with a near constant natural updraft – would love to invistigate the possibility of these on his 14+ acre property. Have you used the horizontal design in rural areas with any success and if not, what limiting factors arose or what would be required to have a successful deployment?

  20. I am an LED lighting system manufacturer and wish to utilize wind powered energy to power our super-efficient LED lighting systems! Please have an associate contact me for further discussions on the possibility of becoming involved in further partnership applications!

  21. Wind power is ridiculous. Whatever happened to the good ol days when you got your power from your local nuclear power plant or coal plant. I am disappointed to see that people actually care about this kind of crap. You only live once, so use all the resources you can, and take a big crap on this planet.

  22. Sir, I’m from Iraq, and here we’re suffering from a severe power deficiency mainly in summer when temp. exceeds 50C.
    please tell me dose your product is found anywhere in middle east and can I use it for operating air-conditioners, air-coolers, or refrigerators.

  23. I’m guessing you are pre promoting a product that you are not ready to market. Am I close…will you at least respond to us.

  24. I live in The San Feancisco Bay area and see the obvious need/use of your product here , and everywhere in the country/world. Please send me at your earliest convenience information on becoming a distributor/ dealer for this part of the country.
    Thank you.

    Bill Martin

  25. All you folks who are trying to contact the company (Aerotecture) on this page should click on the company name in the story at the top of this page instead of leaving a comment at the bottom.

  26. I have a large scale public bulding conversion project in Southern Illinois

    Please send me add contact information

    Thank you

  27. I work for the energy conservation office for the state of Maryland and we are interested in this Technology, and please if possible to provide us with product specification and details.

  28. Hey guys,

    I am the Manager of Technical Service in the e-Health department at Baycrest Centre for Geriatric Care. I recently saw a show on Discovery Channel that featured your technology and I ahve to say it is very impressive.

    We have had to be creative in our cost cutting measure with the recent downturn of the economy and are looking for ways to reduce costs. Our datacentre consumes a fair portion of our monthly electrical bill and was flagged as an area to be reviewed for savings. I then saw the show on Discovery and thought of ways this could be introduced into our environent to save money and as well to help with our green initiatives.

  29. I live in North Central Ohio. Please E-Mail me the costs and specifics for your rooftop installations. Especially the Skystream turbine. Thank You
    Doug .

  30. I am in a very windy location in Utah. I believe that my company could benefit greatly from your product. Will you send me more info via E-mail?I have two buildings that I would like to apply this system to. I require large amounts of energy and I believe this will help cut my cost monthly in half!

  31. I am working on a PROJECT LEAD THE WAY for my high school, where we will be installing wind turbines atop the school to power two science labs about 6kw. Any information you can give me will be greatly appreciated. Thank you Andrew

  32. We are screening various wind power equipments and turbine suppliers in India for Township projects and Residential highrises. We are expecting ths will reduce the dependancy on govt. power supply and effective way of township branding in local cutomers and end users. Pls elaborate on efficiency, cost, life cycle of your product line and weitage if imported in bulk. Pls contact via email.

  33. It was a pleasure to visit your web site and go through your offerings. I am paticularly impressed / intersted in Hybrid energy systems for residences. Kindly let me know if it is viable to have it in India / Bangalore and if you have any installations (and if you can share their performance).

    Grateful if you could share data on wind speed / sun exposure in Bangalore (with source of data) and what output could be expected from the system. You may also advice on the cost.

    Look forward to hearing from you at the earliest.


    Nagendra K Rao

  34. This roof top turbines are very interesting. pl. send me the tecnical detials to implement some energy saving in my home and workplace.

  35. I am extremely interested in alternative energy. I would like as much information on your products for possible sales in the Washington DC area.


  36. Please send more info about this new type of Windturbines. We are building our new headquater in Luxemburg, The Solarwind-building project.
    Looking forward to get information about new, innovativ, efficient technics and materials
    Please send prixe expectations, technical details, installation and delivery information ( to europe)

  37. I would like to schedule a meeting to discuss distributor/installer options. Please reply or call 773-772-8800.

  38. We are building a resort in central VA and are interested in adding two rooftop wind turbine systems. Can someone send me info and help with pricing?

  39. Hi. I am from Ukraine. Our company “Ecothermoengineering ” works with energy saving technologies st the Ukrainian market. We work in different sectors. We find this wind turbine technology very interesting.
    Can you please send me technical information and prices of your product range.
    Thank you in advance.
    Looking forward to further cooperation.

  40. The design feature is comparatively good. Can you give me more details about the performance of this turbine which versus with the length and diameter of the turbine. Also Please send me the details of the generator. It is better if it can produce AC 230 Volt 50Hz without need of an inverter.

  41. Peter,

    That is actually a design feature – the units are not intended to spin quickly. Fast spinning blades are dangerous in urban environments – exactly why wind farms are out in the boondocks. Just think about the birds that would become ground meat if these moved too fast. The slower movements are also meant to be quieter as well.

  42. I am verymuch interested in the windturbine for the home use. I am having small bunglow. I am thinking of installing small wind turbine on the terrace of my bunglow.If you can help, please reply.

  43. Don’t mean to throw a wet blanket on all this- but I drive by those turbines in Chicago everyday–they look great…but don’t seem to spin worth a damn.

    Make sure you get third party testing data before you venture in. I may be wrong…but that’s what we all see.

  44. It is excellent we are too keen to see in india if you could send more litrature about this product and price .and every home will have one all that is required is to produce 2 KW power for home and advance technology in batteries it would revolutnise the world where ever the wind force is avilable in the world.

  45. Sir, I am very much intrested in roof top wind turbine equipment kindly send me the complete detail, costing, installation etc and delearship details on email. Place : Bangalore, India.

  46. ATTN PEOPLE: >>>you have to click the http://www.aerotecture.com link above–or type it in your browser–to actually GO to the site that can sell you equipment or send you information. THIS PAGE IS ONLY NEWS…NOT A COMPANY SITE.

  47. you should try and get these windturbines in Manhattan in the financial district/battery park area near the staten island ferry, it is always terribly windy there. Some of those finanical firms like jpmorgan, may like it as all those comapnies are looking into green/enviro issuess

  48. It’s simply marvellous . please send me the details of Rooftop wind power/Rooftop solar power.

  49. Dear Sir, I live in Northern Canada and see the potential benifits of this type of installation. Can you please forward me information on your product and the possibility of distributor ship for this region of Canada.

    Regards, Shane Wasylucha

  50. I have two 60 silos that I want to convert for wind energy turbine. Please contact me. I also want to start a wind farm in MI on the barn roofs and ground. please contact me at ktmcarr@hotmail.com. Ready to buy.

  51. I have two 60 silos that I want to convert for wind energy turbine. Please contact me. I also want to start a wind farm in MI on the barn roofs and ground

  52. I am interested in selling and installing your wind turbins or wind solar matrix in commercial application, both, new construction and retrofit.

  53. I am extemly interested in this field and would like some information on how to get started. I believe in your product but have no idea what my first step should be. My phone # is 1951 377 2395. My address is 13568 Calico Pl. Chino ,Ca 91710. Any help you could render would be much appreciated. Thank you.

  54. I am very much interested in this Technology, and wants to know well in detail about your Products. I consider it to be the NEXT GENERATION REQUIREMENTS AND BUSINESS. I request you to kindly send us your Product Details – Catalogue via mail or on our Address.

    Thanking you and loking forward to receive your prompt and positive reply.

    RAJKOT – 360 001

    Ph: 00 91 281 222 0731, 662 0731
    Fax: 00 91 281 244 1446
    Email: samson_priyanka@yahoo.com

  55. I am assembling a budget for a new construction project in Highland park
    The project is calling for one of your wind turbines,
    can you please send some literature on who is installing these, as well as the technical data as to how much they weigh etc. etc.

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