Used to align oil pump to the cam support plate. Helps reduce oil pump scavenging inefficiency due to oil pump misalignment. Also used to align tappet blocks on L76-99 B.T. models so lifters run true on the camshaft. Sold in a 3-pack, so you can align 3 holes of a lifter block, put in the first screw, and replace each alignment screw with the other mounting screws one by one until the lifter block is fully installed. - 1/4-20 threaded - Nitro-carburized heat treatment means these tools will last forever - 100% made in USA / Fitment: Oil pump: 99-17 Twin Cam (NU); Tappet blocks: L76-99 B.T. (excl. Twin Cam) (NU).