This is a Dremel EZ Lock Diamond Wheel. FEATURES: A metal wheel completely coated with fine diamond particles for working with hard materials Designed to last and not lose its shape or break Easy installation-just pull, twist and release Rated for tile cutting INCLUDES: One Dremel EZ Lock Diamond Wheel REQUIRES: Installing on mandrel and fastening to rotary tool SPECS: Diameter: 1/2" (12.7mm) cnh 12/10/08 ir/jxs