Greenlee 60287 Square Punch Unit, 1-7/9-Inch : Amazon.ca: Tools & Home Improvement
Southwire Knockout Punch Sets at Lowes.com
Square 45mm x 45mm 1/16 DIN Panel Meter Punch Dies 1.772" x 1.772" : Amazon.ca: Tools & Home Improvement
Square Knockout Punches
Greenlee - 0.945 Inch Hole Length x 0.945 Inch Wide, Square, Knockout Punch Unit - 04224838 - MSC Industrial Supply
927803-7 Greenlee Knockout Punch and Die Kit: 14 ga Sheet Metal Capacity (Steel), 3/4 in Nominal Size, Square | Imperial Supplies
Square Hole Punches - Lee Valley Tools
Greenlee 1 Inch Hole Length x 1 Inch Wide, Square, Knockout Punch Unit Hydraulic and Manually Operated, 14 Gauge Max in Mild Steel 60016 - 04224846 - Penn Tool Co., Inc
Alfra 1/2" X 1/2" Square Punch & Die Set - Panel Punching
FORCE LOGIC Knockout Tools, Tool Sets and EXACT Dies | Milwaukee Tool