ARP Pro Series Head Stud Kit - GM LS Engine up to 2003ARP Pro Series Head Stud Kit Suits GM LS Chevrolet Small Block LS1 Pro Series thru to 2003 These Pro series studs 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 12 point nut, and all kits come complete with hardened parallel washers for an even load distribution and accurate torque readings. Kit # 234 4316