The Milwaukee 49-94-4520 is a 4-1/2 in. x 1/4 in. x 7/8 in. Grinding wheel (Type 27). Milwaukee's comprehensive offering of grinding and cutting wheels consists of 45 unique products ranging in diameters from 4-1/2 in. to 14 in., with Arbor configurations of 7/8 in., 20 mm, 1 in. and 5/8 in. 11. Milwaukee's abrasive offering is manufactured using three types of abrasive grains, aluminum oxide, silicon carbide, and zirconia alumina, providing products for general purpose to specialized high performance applications.