The Forney 4-1/2 inch Type 1 aluminum oxide metal cutting wheels. Designed for metal cutting, metal abrasion, body work, metal fabrication and general repair work. Used on ferrous materials. Maximum RPM 13580Type 1 steel cutting wheelDesigned for metal cutting, metal abrasion, body work, metal fabrication and general repair workUsed on ferrous materialsDesigned to be used on right angle grinders onlyISO 9001 certifiedWheel Size: 4-1/2 in.Thickness: .040 in.Arbor: 7/8 in.Spec: A60T-BF