4.5” x 4” x 3/4” quad key shaft Surface Conditioning Abrasive Drums by Black Hawk Abrasives are designed to clean, blend, finish and condition metal with ease. Each 4-1/2 inch non-woven drum is manufactured with premium nylon webbing infused with aluminum oxide grains centered around the 3/4” keyed shaft. The porous, non woven structure promotes airflow and resists loading which prolongs the useful life of the wheel and reduces heat buildup which may stain or distort work pieces. The 4” surface finishing drum by BHA offers a greater sanding surface area compared surface conditioning quick change or flap discs making them ideal for large jobs. The 4.5 inch black hawk abrasives non woven surface conditioning flap wheel drum is uniquely suited for light paint and rust removal, creating a satin finish on some metals, as well as final stage conditioning before buffing begins. This drum is affixed with a hub that fits 3/4 inch keyed shaft that attaches to surface finishing machines and linear grinding machines (A.K.A. Burnishers, burnishing machines, contouring grinders, etc.) and is available in 60 grit, 120 grit, 240 grit and 320 grit.