special type grease fitting: button head or double head available size:m10x1,m8x1,m6x1,1/8"bsp,1/4" ... 1200 designs straight, angled-90º, 45º hydraulic, button head and concave types. Self forming threads and Drive-In Shanks make installation easy ... both metric and imperial grease fittings and zerk fittings double head grease fittings 1/8"bsp