This is the best center marker on the market. Show it the end of your stock, give the piece a whack, rotate 90° and do it again. You have instantly marked sharp, crisp lines that identify center with great accuracy. The marker is drilled for permanent mounting near your lathe, so you don't have to hold both the marker and your work while searching for a pencil with your third hand. Its sharp steel marking blades cut distinctly into any stock, providing not only precise centering lines but a natural place to seat your drive center as well. It works on round, square or polygonal stock up to 6" across.