AMZCNC Manual Knockout Punch Kit, Heavy Duty Metal Sheet Knock Out Box Hole Cutter Conduit Punch Driver Die Set ((Conduit Hole Size) 1/2"~1-1/4" Knockout Punch kit)

Worked well

These worked perfectly. The only thing that would make them nicer is if the dies had flat surfaces so open end wrenches could be used to open them back up after punching the hole. As it is, we had to use locking pliers to do it. These are made of dies that are so hard that we actually wore out once set of locking pliers by wearing the teeth down, so I had to buy more pliers! I feel that flat surfaces to make the dies fit open end wrenches would have avoided that problem.

Drill two pilot holes in Hoffman pull box.Enlarge pilot holes for the drawstud.Knock out the two holesDone in five minutes.Works just like the 'Green' brand but only time will tell how long it lasts.

I was installing an electrical system for a 3200 sqft mixed-use building. Everything was surface conduit with 4” boxes and pull boxes. Multiple boxes needed a hole or a different size hole and these punches came to save the day. I imagine a hand wrench or socket set could be used, but I used cordless impact wrench and it gave me the hole I needed within 15 seconds. It worked well in a tight space and was way better over a hole saw.I’d punch out the smaller plug and use the hole cutter for the larger needed hole. (1/2 knockout to get 3/4; 3/4 knockout to get a 1”). I didn’t try it, but I think the 3/4 punch bolt is larger so you can’t use a 1/2” knockout for a 1” hole.

The functionality of this is spot on....but someone didn't think to include a storage box for this set.