To maintain a reputation for "zero defects", ensure optimal quality control and produce fasteners of exceptionally high quality. ARP controls all aspects of the manufacturing process, with all operations performed in the home where they can be closely monitored. ARP takes exceptional measures to produce the very best products of their kind on the market today. Now you can help prevent intake manifold leaks with ARPs high quality fasteners. These conventional hex bolts are made from chrome moly steel with a black oxide finish and have a rating of 170,000 psi. They are precision crafted with rolled threads for optimal thread engagement and to prevent galling while promoting more consistent torque loading. The wide underhead flange and the accompanying discs ensure even load distribution and thus facilitate the optimal sealing of sealing surfaces. This kit is specially designed for select Chrysler applications (small block, 273-440 wedge, uses 3/8 inch socket).