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. ARP takes extraordinary steps to produce the very finest products of their kind on the market today. These premium quality oil pan bolts are manufactured from black oxide finished chrome moly steel, feature conventional hex style heads, and come complete with washers.