This knockout punch makes a clean 22mm hole in most metals, including stainless steel brewpots and kegs. Perfect for punching valve holes, and also punches holes in sheet metal that fit all beer shanks, so this punch is a great help when fabricating a Keezer or Kegerator.
To use, drill a 10mm wide pilot hole with a step drill or drill bit (not included). Place the bolt through the hole and thread the die and the punch together. Use a wrench to tighten the bolt until you hear a click sound, which means the hole has been cut. Remove assembly and discard slug.