These wire cup brushes are designed for high performance removal on flat and large surfaces. They are made from top quality oil hardened and tempered wires that are precisely positioned for perfect balance and longest brush life. Improved construction ensures maximum operator safety and fast brushing action. All cup brushes are equipped with threaded arbors for quick and easy mounting.Feature: Aggressive brushing action Perfect balance Safety supporting ring Smooth action Top quality wire Application: Brushing Deburring Removal Material:SteelSpecifications: Model # Diameter Arbor Wire Wire Type Max RPM 13-G 304 3" 5/8"-11" 0.02" Knot-twisted 12,000 13-G 504 5" 5/8"-11" 0.02" Knot-twisted 8,600 13-G 604 6" 5/8"-11" 0.02" Knot-twisted 6,800 * All Pictures Shown Are For Illustration Purpose Only. Actual Product May Vary Due To Product Enhancement.