Greenlee® Speed Punch® knockout punch, replacement, 2.416 in dia cutting, 2 in, carbon steel, nickel plated, applicable materials: 10 ga mild steel, aluminum, fiberglass and plastic. Greenlee® 7212SP-2P Speed Punch® Knockout Punch, Replacement, 2.416 in dia Cutting, 2 in, Carbon Steel, 10 ga Mild Steel