ARP Balancer Bolt Kits | Multiple Ford Fitments (150-2503)Square Drive Balancer Bolt Kit by ARP As the crankshaft flexes, the balancer absorbs incredible amounts of energy. ARP balancer bolt kits will ensure that your balancer is locked into position. They feature a 12 point head that accepts a deep socket to eliminate the fear of stripping the head. Features Thread Size: 5 8 in. 18 Underhead Length (in.): 2. 050 in. Head Style: Square drive Washer Included: Yes Fastener Tensile Strength (psi): 200,000 psi