ARP 134-3601 Cylinder Head Bolt Kit for Chevrolet Small Block SBC 305 350 383 400 EnginesThese ARP High Performance series head bolt kits are tough! They are rated at 170,000 psi 15 percent stronger than Grade 8 fasteners. They come available with hex heads or reduced wrenching 12 point heads that eliminate the need for valvetrain removal when re torquing cylinder heads. Fastener Style: Bolt Head Style: Hex Fastener Material: Chromemoly Fastener Finish: Black oxide Washers Included: Yes Cut to Fit: No Quantity: Sold as a kit.