This addition to your plasma cutting machine will assist you in cutting holes from 5/8" to 36" in diameter. It can be used as a guide for straight and irregular cuts by using the wheels provided. Set up the plasma guide for cutting medium to large circles by installing one wheel on the plasma body. Because this tool is so well balanced, a wheel on the plasma body is not necessary when cutting small (5/8" dia.) holes to (4"dia.) medium holes. It's as simple as centering the punch where you want the center of the hole, and then, setting the radius of the hole from the pointer on the hex arm to the center of the plasma torch. That's it; you are ready to cut.