ARP 135-2501 Hardened Balancer Bolt Kit for Chevrolet Big Block 396 427 454 502 Engines

Harmonic Balancer Bolt, Chromoly, Black Oxide, 12-Point, Chevy, Big Block, Each Thread Size: 1/2-20 in. RH Underhead Length (in): 1.550 in. Head Style: 12-point Washer Included: Yes Fastener Yield Strength (psi): 200,000 psi Fastener Material: Chromoly Fastener Finish: Black oxide As the crankshaft flexes, the damper absorbs incredible amounts of energy. These damper bolt kits from ARP will ensure that your balancer is locked into position. They feature a 1/4 in. thick wide-area washer and an extra-tall, 12-point head that accepts a deep socket to eliminate the fear of stripping the head.