Now you can use premium quality ARP fasteners to install most anything on a car, boat, or trailer. Manufactured from heat-treated 8740 chrome moly steel with a black oxide finish and nominally rated at 170,000 psi tensile strength, this hardware provides a substantial extra margin of safety over Grade 8 hardware. The five bolts in this package each feature a compact 12-point style head, have a diameter of 3/8", a standard thread pitch of 16, an under head length of 1.500, and the wrenching is 3/8.