I need to eyeball mine. At first I was just trying to remember all the steps to use it, and never thought to examine it. Barb if it works as it should, you will forget about blems pretty quick. Only tool like it, and once the patent is gone everyone will be making something similar, but like a Fein multi tool, it will have been used and loved by you that even at a third of the price you will still be glad you bought one.