A quick and easy way to cut clean metric sized holes in sheet metal up to 16 gauge the special design allows even load during cutting and produces a burr free hole that needs no extra finishing heat treated cutting edges with black anti corrosive surface finish to prevent rusting all punches are sold singly without key which should be ordered separately thread the punch onto the hexagonal screw and then pass the hexagonal screw through the hole position the die on top of the die nut and then scr