Primary Chaincase Gasket, for use on BSA models: C15, B50. Triumph models: TR25, T100, T21, 3TA & 5TA. O.E.M: 71-1419 / 70-3832 / 40-0421.Primary Chaincase Gasket, 40-0421 / 71-1419 / 70-3832. GAS 93SKU: 71-1419 / 70-3832 / 40-0421£2.30PriceQuantity*Add to Cart