This hole punch is for use with the Bowsmith Emitters as well as the Micro-Flapper Emitters.
Use the metal area to punch a proper size hole in your 1/2 inch tubing.
Then you can use your “Insert Tool” ACU-38 to push your Micro-Flapper emitters in. You can also just use pressure from your hand.
There is not an insert tool available for the Bowsmith emitters. These are large enough to push in by hand.