Cast iron construction just like the original Wagner Lockheed type it replaces Painted Silver The complete assembly includes all internals, cap and rubber boot. 3/4″ Bore Use Only DOT 5 Brake Fluid Accepts 3/8"-24 Inverted Flare Brake Line Fittings Only Fits 1958-(Early)1979 Harley FL & 1971-(Early)1979 Harley FX Replaces HD# 41761-58 & 41761-78 Note: Disc brake models require the removal of the rubber coated reduction washer and the cup valve.