Stage 8 (8906B) 8mm-1.25" x 30mm Locking Header Bolt Kit for Ford 4.6L/5.4L Grade 8 bolts will not stretch when hot Duplex nickel finish for a superior look and corrosion resistance Double Hex Head includes 3/16 inch recessed Allen Head for easy installation Removable and reusable Can visually inspect - no need to put a wrench on to check tightness