The taper on NPT threads allows them to form a seal when tightened

but WD-40's combination of aerosol propellant and organic-based lubricant is perfect for sliding tight grips onto clean metal tubes

Reproduction of tappet screws OEM# 18555-36 and locknuts 18570-38 used on 1936-1952 Harley-Davidson Big Twins

Fits 1936-1939 Knucklehead

Chrome plated plated duplicate of OEM# 720 allen style plug used on all Harley-Davidson 1970-up

#3530-6 Spotlight Clamp Kit 1938-1961 Harley-Davidson Models- Chrome Plated Subcategory_Fork Hardware The taper on NPT threadsReproduction chrome plated OEM# 68702 38 clamps, original finish 68707 38 screw, nut and lockwasher. Used on 1938 1961 Harley Davidson models. Made in Ohio, USA.