This new three-sized jewelry hole cutter/puncher is great for making cold connections. The punches are heat treated and with the screw action, you can create clean holes in soft metals up to 18 gauge in thickness without deforming the metal. With the unique design, it offers more flexibility, accurate hole placements and depth. By attaching the adjustable guide plate to the bottom of the punch, you can also create multiple pieces with holes at the exact locations on each piece. Hole sizes: 1/16 inch (1.58mm), 3/32 inch (2.38mm) and 1/8 inch (3.17mm).