Product image may look slightly different from actual product appearance. Pro Series Cylinder Head Bolt Kit. Cylinder Head Bolts, Pro Series 12-Point, Chevy, Small Block, Gm 18 Degree High Port Heads, Kit. The Pro series cylinder head bolts from ARP are cold-forged to ensure molecular integrity. They are heat-treated prior to thread rolling and machining, and are rated at a whopping 190,000 psi. The Pro series are also available with hex and 12-point heads. All kits come complete with hardened parallel washers for even load distribution and accurate torque readings. Our Best Price Guarantee is part of our commitment to always offer you the lowest possible price. Should you find…