Earl's Racing Products head bolts are made from premium quality 170,000 psi chrome moly alloy steel (about 15% stronger than Grade 8). These bolts have a reduced wrench size (choose from 12-point or hex head) for extra socket clearance (provides extra clearance to rocker arms when re-torqueing heads). The wide flanged head provided more support for the extra thick chrome moly washers. These head bolts are reusable and are the ideal way to upgrade the performance of your engine, and eliminate the hassle and cost of replacing factory style torque-to-yield style bolts each time the cylinder heads are removed. Black oxide finish & sold in complete engine sets. Made in the USA.