To maintain a reputation for "zero defects", ensure optimum quality control, and produce fasteners of exceptionally high quality, ARP controls all aspects of the manufacturing process, performing all operations in-house where they can be closely monitored. This harmonic balancer bolt kit is a good example of how ARP takes extraordinary steps to produce the very finest products of their kind on the market today. As the crankshaft flexes and twists, the balancer absorbs incredible amounts of kinetic energy. To ensure that the balancer is locked in position, ARP has developed these ultra strong 200,000 psi bolts that let you exert maximum clamping force. Special features include the 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.