IVY Classic 39052 4-Inch x 1/2 - 3/8-Inch Arbor, Carbon Steel Crimped Bench Wire Wheel - 0.012-Inch Coarse, 1/Card Removes rust, dirt, scale, paint and cleans welds Precision balanced to eliminate vibration Tempered carbon steel bristles for long life Wire Diameter: Coarse 0.012-inch, Face Width: 1/2-inch Wheel Diameter: 4-inch, Arbor: 1/2 - 3/8-inch, Max RPM: 4,500