Klein Tools 53728SEN Optimized Design 10-Guage Mild Steel Knockout Punch Set with Black finish, 1/2-Inch

It's a well made hole punch. One reservation - it is specified as a 1/2" (12.7mm) punch, that's what it says on the packet. Unfortunately on the punch body itself it is stamped 1/2" Conduit. The actual hole it makes is around 7/8" (22.4mm). this made it not useful for the purpose I bought it for. I will probably keep it because it may come in useful sometime, but I guess they count on this attitude when the omit the word "Conduit" on the packaging.

Con un buen huso esta herramienta puede durar suficiente

Outil de très bonne qualité

These tools work well, but be aware the sizes listed are not the actual diameters of the holes they make. They make "trade size" knockouts for 1/2" and 3/4" conduit fittings (well known to electricians). Also, these tools require "pilot holes", which are smaller holes drilled through the center of desired larger hole. A "draw bolt" runs through the pilot hole to guide the punch. Make sure to keep the threads on the draw bolt well cleaned and lubricated since they shoulder a lot of force. I just did a couple test punches and measured with calipers: The 1/2" punch (53728SEN) needs a 3/8" pilot hole, and makes a 7/8" (0.885", 22.5mm) hole. The 3/4" punch (53727SEN) needs a 3/4" pilot hole, and makes a 1-3/32" (1.095", 27.8mm) hole. The description really should include this information.

Does the job as intended. Perfect for 1/2" conduit connections. Excellent price and good service. I am keeping it for future use but was actually looking for a 1/2" punch and this device makes a 7/8" hole. Well known to electricians but would be helpful if the fact was included in the description.