Size: Overall length 100mm Pitch: 5mm Quantity: Set of 4 (1, 2, 4, and 6 prongs) Prongs 1 and 2 are suitable for punching holes in curved parts, while prongs 4 and 6 are suitable for punching holes in straight parts. Place the diamond chisel vertically on the leather and strike it with a hammer or similar tool. To prevent rust, oil has been applied in advance, so please wipe it off before use. Due to the nature of the tools, there may be small scratches or stains. Please purchase only if you understand this.