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 timing cover 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. These bolts are manufactured from ARP 300 polished stainless steel, which is rated at 170,000 psi. They feature compact 12-point style heads and come complete with high quality washers.