BHA - Black Hawk Abrasives 3" Quick Change Unitized Discs are designed for effortless and efficient deburring, blending, cleaning, finishing or polishing in a compact size; ideal for work in confined spaces. Unitized wheels feature compressed, and cured layers of non-woven nylon fibers impregnated with abrasive grains. The structure of these unitized wheels allows for bi-directional use (they can be run in either direction), reduced loading, and minimal heat buildup which extends the life of the disc and protects the work piece. These unitized discs are less conforming than other surface preparation wheels to ensure a more consistent and uniform finish. Each quick-change unitized disc is constructed with a Type R, Roll-on attachment to reduce changing time decreasing work down time. BHA Unitized quick change discs are available in a variety of combinations of densities, abrasive material, and grades including 2SF, 3SF, 2AM, 6SF, 6AM and 8AC. Please check the details below and select the unitized disc that best suits your needs: Density = (2) low - (8) high Abrasive Material = (S) Silicon Carbide or (A) Aluminum Oxide Grade = (F) Fine, (M) Medium, (C) Coarse