Neiko 02624 Classic Numbers & Letters Punch Set | Hardened, Heat Treated Steel | 36 Piece Set Heavy duty design punches can make permanent imprints in metal as well wood, leather, plastic and more Created with hardened, heat treated #45 carbon steel for increased durability and longer service life Perfect for hobbyists or jewelers customizing crafts, marking valuables, stamping name plates, punching scratched & worn serial numbers \Metal alphabet punches are on a 1/4" (6mm) square shank for use as impact hammer bits Comes in hard plastic case for organization, storage; Includes letters, numbers, ampersand ("&"); factory greased and ready to use