• Set Includes: 2.5, 3, 4, 5, 6, 7, 8, 9 & 10mm • Chrome Molybdenum (Cr-Mo) alloy steel for strength & durability • Precision ground flute and cutting edge for clean accurate cutting • Non-slip knurled handle for a secure grip • Ideal for punching holes in leather, gasket material, rubber sheet, cardboard & soft plastic • Easy to use, just place punch in position and strike firmly with hammer or mallet