English: Extruded holes in sheet metal with the punch and die used to create them. The left hole was punched without using a pilot hole. A 1/16" (1.58mm) pilot hole was used in the center and a number 58 (0.042" or 1.06mm) pilot hole was used on the right. Material: 16-gauge (0.062" 1.6mm) hot rolled mild steel. Die (right top): Roper-Whitney type O, 7/32" (nominal 5.55mm). Punch (left top): high-speed steel 0.113" (2.87mm) diameter with a 90° point.