LS HEADER STUD KIT BOLTS STAINLESS STEEL LSX LS2 LS3 LS6 LS7 4.8 5.3 6.0 6.2L - For Installation of Headers / Exhaust Manifolds to Cylinder Heads. Fits GEN III, IV LSX (LS1 LS2 LS3 LS6 LS7) Chevy V8 Engines. Fits GEN III, IV LSX (4.8 5.3 6.0 6.2L Vortec) Truck Engines. - SPECS: Hardened 304 Stainless Steel; (12) M8 Studs (polished); (12) M8 Hex Locking Flange Nuts; Accepts #4 Allen Key / Allen Socket for Install.