Hight Performance Chevrolet 180,000 psi 3/8-24 Rocker Arm Studs Manufactured from tough 8740 steel, featuring a large ground radius fillet to provide increased support to the stud shank, effectively eliminating bending and subsequent breakage. All studs are precision machined with rolled threads and heat treated for tensile strength of 180,000 PSI then finished in black oxide.