Cal Hawk Tools AZNS3P Nut Splitter Braker Set (3 Piece) Hardened, tampered & forged chrome vanadium steel chisels and screws Large screw drives Sizes: 5/16" - 1/2" (9-22mm), 1/2" - 5/8" (12-16mm), 5/8" - 7/8" (16-22mm)