Original style gas cap for 1939-1964 Ford tractor models. For all models of Ford tractors prior to 1964.

Diesel fuel tank cap for Ford tractor models: 2000, 3000, 4000, & 5000,(1965-75); 2600,3600,3900,4100,4600,5600,5700,6600,6700,7600 & 7700, (1975-81); 8700,9700,TW10,TW20 & TW30 (8/1975-82); 2810,2910,3910,4110, 4610SU, (1981-2/90); 5610,5900,6610,6710,7610,7710, (1981-10/91); 7810 without auxiliary tank,7910,8210,TW5,TW15,TW25 & TW35, (1982-2/90); 8530,8630,8730 & 8830, (1990 & UP)