Premium performance, ceramic aluminum oxide grain.Very uniform, high density grain structure is extremely durable and self sharpening for long life and cooler cut.Combines fast stock removal with long life for tough cutting applications.Ideal for foundry applications (gates, risers)., Unique, thin Type 27/Type 42 shape can be used on all angle grinders in accordance with ANSI B7.1.Special bond formulation offers the fastest cutting, longest lasting thin wheels.Externally reinforced with fiberglass layers to provide ultimate safety in a thin wheel.Reusable 5/8-11 adapter for use on Type 27 / Type 42 reinforced wheels with a 7/8 arbor, and a maximum diameter of 5" and a wheel thickness of .045" to 1/8" is available in accessories. Part #95055.