Punch Discsizes : 17 | 18 | 18.2 | 19 | 20 | 22.5 | 24 | 26 | 26.7 | 32mm. ble to cut holes in plastic bumpers up to 5mm in thickness, the kit includes a 5/16" HSS drill bit to create a guide hole and varied discs that can punch holes in the following sizes: 17mm, 18mm, 18.2mm, 19mm, 20mm, 22.5mm, 24mm, 26mm, 26.7mm, & 32mm.