If you are in need of an efficient Pipe Cutter these are a good type. I have tried other pipe cutters and this one is the type that works best for me. It cuts through copper and plastic leaving a clean neat cut.
You put the pipe in the unit or slide the unit on the pipe and then tighten the Thumb Screw a bit. Turn the unit, then tighten the thumb screw some more. Keep doing this until the pipe breaks off – is cut right through.