This head stud kit is required when using Edelbrock LS-R cylinder heads #770468 and #770469 on GM LSX engine blocks. Includes 10 7/16" long studs, 10 7/16" short studs, 8 5/16" exhaust studs, 10 5/16" intake flange studs, 8 5/16" valley studs, 20 7/16" washers with nuts and 26 5/16" washers with nuts.