Forney 72310 Grinding Wheel, Type 27 Industrial Pro Metal with 5/8-Inch-11 Threaded Arbor, ZA24R, 7-Inch-by-1/4-Inch Zirconium grain metal grinding wheel Designed for metal grinding, metal abrasion, body work, metal fabrication and general repair work Used on ferrous materials Industrial Pro wheels are our highest quality and last longer than standard wheels For use on right angle grinders only