High performance, ceramic aluminum oxide grain.Uniform, high density grain structure is extremely durable and self sharpening.Fast cutting with extremely long life., Unique, thin Type 27/Type 42 shape can be used on all angle grinders in accordance with ANSI B7.1.Designed to provide very long life for fewer wheel changes and less downtime.All sizes reinforced with the highest quality fiberglass for maximum safety and performance.Proprietary bonding system allows for faster, burr free cuts.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.