4.5” x 4” x 3/4” quad key shaft Flap Wheel Abrasive Drums by BHA - Black Hawk Abrasives are designed to debur, grind, blend, or removal flash, scale or rust on large surface areas. These flap wheel drums feature x-weight cloth that is coated and resin bonded with aluminum oxide grains and offer a more aggressive alternative to the interleaf or surface conditioning drums. The sanding flaps are displayed in a fan like pattern which allows the drum to grind quickly while exposing new, sharp abrasive grains, thus providing a consistent cut throughout the useful life of the abrasive. This fan like design also provides flexibility and when used with sufficient pressure this drum is excellent at removing paint, heavy pitted corrosion or removing material to level off an uneven work piece. The 4 inch wide flap drum by BHA is able to sand, grind and finish over a greater sanding surface area compared flap discs for angle grinders. With it's sturdy and abundant sanding flaps, the 4-1/2 inch black hawk abrasives flap wheel drum is uniquely suited for blending scratch patterns or parting lines, cleaning welds, oxidation removal, de-scaling heat treated aluminum, removing rust and paint, and providing a nice grain that you can finish with a finishing drum at a later stage. 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 and 120 grit.