500 Pack Cut-Off Wheels. Ideal for cutting all types of steel including stainless and most other metals. Tough aluminum oxide abrasive gives quick and clean cuts while extending tool life. Designed for use with angle grinders up to 13,300 RPM. The thin cutting profile minimizes material loss and maximizes cutting speed. Fiberglass mesh reinforced for added safety. Diameter: 4-1/2 inches. Arbor diameter: 7/8. Abrasive: Aluminum oxide. Grade: T (hard). Bond: BF Resin bonded (reinforced with fiberglass mesh). Type: 1 (flat). Max RPM: 13,300 RPM.