A60S - General Purpose. So Unique it has a patent. Thin .045 width. Special aluminum oxide grain. Hard bond for extremely long life. Fast, burr-free cutting. Ferrous and/or non-ferrous metals (iron, steel, welds, etc.). Specifications: Max RPM - 12200. Tech Info: Unique, thin Type 27 shape can be used on all angle grinders in accordance with ANSI B7.1. Special Aluminum Oxide formulation offers the fastest cutting, longest lasting thin wheels. Externally reinforced with fiberglass layers to provide ultimate safety in a thin wheel.