| ABC Motors Ltd | Hersham, | England, |
UK |
| Alvis Car and Engineering Co Ltd | Coventry, | England, |
UK |
| Armstrong Siddeley | Coventry, | England, |
UK |
| Bristol Aeroplane Company | Filton, | England, |
UK |
| Buick Motor Division of General Motors | Detroit, | Michigan, |
USA |
| Caterpillar Tractor Co | Peoria, | Illinois, |
USA |
| Cirrus Engine Section of Blackburn & General Aircraft Ltd | Brough, | England, |
UK |
| Curtiss-Wright Corporation | Charlotte, | North Carolina, |
USA |
| Daimler-Benz AG | Munich, | Bavaria, |
Germany |
| de Havilland Engine Company | Leavesden, | England, |
UK |
| Deere & Company | Moline, | Illinois, |
USA |
| Farm Horse Tractor Works (SD) | Hartford, | South Dakota, |
USA |
| Ford & Son Tractor Company | Dearborn, | Michigan, |
USA |
| General Electric Aviation | Evendale, | Ohio, |
USA |
| GW Elliott & Son | De Smet, | South Dakota, |
USA |
| International Harvester | Chicago, | Illinois, |
USA |
| J I Case Threshing Machine Co | Racine, | Wisconsin, |
USA |
| Junkers Motoren (Jumo) | Dessau, | Saxony-Anhalt, |
Germany |
| Link Aviation Devices, Inc | Binghamton, | New York, |
USA |
| Marquardt Aircraft | Venice, | California, |
USA |
| Nicholas Powers | New York, | New York, |
USA |
| Pratt & Whitney | East Hartford, | Connecticut, |
USA |
| Righter Manufacturing Company | Glendale, | California, |
USA |
| Rolls-Royce Ltd | Barnoldswick, | England, |
UK |
| Rolls-Royce Ltd | Derby, | England, |
UK |
| Sumner Iron Works | Everett, | Washington, |
USA |
| Turbomeca | Bordes, | Aquitaine, |
France |
| Westinghouse Electric Corporation | Monroeville, | Pennsylvania, |
USA |
