DEPRESSED CENTER GRINDING WHEEL. TYPE 27A (THIN METAL CUTTING). ALUMINUM OXIDE GRIT AND PREMIUM RESIN BOND FOR PROFESSIONAL RESULTS. EXTRA THIN THICKNESS FOR FAST CLEAN CUTS IN ALL FERROUS METALS AND STAINLESS STEEL. FIBERGLASS REINFORCED FOR SAFETY AND INCREASED DURABILITY. SPEC A60T GRIND THIN METAL. 15 300 SAFE RPM.