3M RADIAL BRISTLE DISC BRUSH ASSORTMENT 21 Pc. SET 3/4" Dia. 3 each ALL 7-GRITS (E 1) 3M RADIAL BRUSH BRISTLE DISCS 3/4" 21 piece SET These are the unique 3M Radial Bristle Discs a new type of abrasive that is superior to sandpaper, flap wheels, or other types of sanders, brushes, or abrasive wheels. The 3M bristle materials are long lasting and very effective. The 3M Cubitron and aluminum oxide grains embedded throughout the plastic bristles make them very long lasting. Their flexible bristles can reach into areas with detail and irregular, curved, or flat surfaces. Bristle Discs can be stacked, use as many discs as needed on rotary miniature mandrels, use them like natural bristle brushes, without any compounds - which is already impregnated in the disc material. The different colors of discs designate the grade. Depending on the application, you will want to stack between three and six discs. The discs are very flexible, cool running, long lasting and provide a uniform finish.