For Small Block Chevrolet applications with Brodix Pontiac design heads, 40/60 stud spacing, spring loaded design with 3/8" studs; Solid bar, one-piece design ties studs together and properly locates them; Constructed of 6061-T6 aluminum for light weight and anodized for durability; Kits come complete with hex head adjusting nuts , interlocking set screws and all hardware;