Replacement wheel used for splitting the point on HSS and cobalt drill bits when used with V390 Tool-Drill Sharpener, Item# 3316390. Sharpens approx. 2000 bits before needing replacement. Long-lasting, 180-grit wheel does not require dressing. U.S.A. Accessory Type Splitting wheel, Product Type Accessory, Grit 180, Usage DIY to professional level, Wheel Diameter in. 3.