Greenlee Slug-Buster 7238SB Manual Knockout Punch Die Kit, 10 ga Capacity, For Use With Battery Powered/Hydraulic Ratchet Driver and 3/8 in and 3/4 in Draw Stud, 1/2 to 2 in Conduit/Pipe, Mild Steel
Greenlee Intelli-PUNCH Battery-Hydraulic Knockout Kit with Slug-Buster — Orka
For punching holes in mild steel, aluminum, brass, copper, fiberglass and plastics