The D21 Ball End Rotary Tool features a 7 mm round burr and comes in 600 grit for autographing or personalizing pottery pieces. These diamond rotary tools are incredibly long-lasting with proper use. As the tool wears down, a new layer of diamonds is exposed.
Note: For longevity, use water, high speed and gentle pressure. Overheating the tool will greatly decrease tool lifespan and change the tool shape. "Let the diamonds do the work."