LICHAMP Manual Knockout Punch Kit, Heavy Duty Metal Sheet Knock Out Box Hole Cutter Conduit Punch Driver Die Set : Amazon.ca: Tools & Home Improvement
AMZCNC Hydraulic Knockout Punch Electrical Conduit Hole Cutter Set KO Tool Kit 1/2 to 4 inch (15T(1/2"-4")) : Amazon.ca: Tools & Home Improvement
Greenlee Slug-Buster 735BB Manual Standard Round Knockout Punch Die Kit, 10 ga Capacity, For Use With Greenlee KRW-1 High Leverage Ratchet Wrench, 1/2 to 1-1/4 in Conduit/Pipe, Mild Steel