Features and Benefits: Grinds, cuts and under cuts – Go where no wheel has gone beforeAllows access to hard-to-reach areasOut performs standard grinding wheels in all ways; maintains diameter, lasts longer and cuts faster with low odor and debrisFor grinding, deburring, surface prepping, cutting sheet metal, fiberglass and more3/8 arbor with shank adapter 30,000 rpm max.The 3 in.;, 3-in-1 Diamond Grinding Wheel’s innovative, three-dimensional, diamond-abrasive coating allows for fast cutting, back cutting, gully cutting and bead finishing with far less sparks and odor. They are aprofessional solution for professional metal workers. Diamond-abrasive products are more expensive to manufacture than standard abrasive discs. However, they last longer and perform better while maintaining their size and shape throughout their cutting life.