The Edelbrock Head Bolt Kit, manufactured by ARP, contains a complete set of the highest quality head bolts and hardened washers available. These head bolts are cold-formed to ensure molecular integrity and heat-treated prior to thread rolling and machining. This head bolt kit has a 12-point head and is designed for use with Edelbrock heads: EDL- 60919, EDL-60929, EDL-60149 and EDL-60189. They have a reduced head, which eliminates the need for valve train removal for cylinder head re-torqueing and permits the use of larger diameter springs. The hardened and parallel-ground washers are included and they are rated at 170, 000 PSI.