Ajax
- Ajax Motor Manufacturers, Birmingham, 1922-1924
- Ajax of Italy - these were rebranded Astoria machines fitted with AJS engines, 1930s
- Ajax of Belgium in the 1950s, engines from Sachs and NSU.
- Ajax Motor Vehicle Co. New York City, New York USA 1901-1903
- Ajax Cyclecars, Briscoe Freres, Neuilly, Billancourt 1913-1914
- Ajax Motors Co. Seattle, Washington USA 1914-1915
- Ajax Motors Co. Racine, Wisconsin USA 1925-1926
- Ajax. Dr. G. Aigner Switzerland 1906-1910 (Autos)
- Royal Ajax, Silver Queen Cycle Co, London 1904-06
- Royal Ajax, British Cycle Manufacturing Co, Liverpool, 1904-06