ARP 234-2503 LS Engine Crankshaft Harmonic Damper Bolt Kit

LS engine crankshaft harmonic damper bolt kit for all LS engines except LS7 and LS9. 12-Point Head, 1-1/16 Socket, M16 x 2.0 Diameter Thread Size, 4.325 Under Head Length

From ARP: As the crankshaft flexes and twists, the balancer absorbs incredible amounts of kinetic energy. To ensure that the balancer is locked in place, ARP has developed these ultra-strong 200,000 psi bolts that let you exert maximum clamping force. Special features include 1/4' thick, wide area washer and an extra tall 12-point head that accepts a deep socket and eliminates the worry of stripping the head.