The desired length of the strip can be torn from the roll for a specific application. Most grades have a light, J-weight cloth backing that provides the flexibility needed to conform to circular edges, angles, or other contours. Rolls in grades P50 or P60 have a slightly stiffer X-weight backing suitable for more coarse sanding applications. Cloth remains durable even when bent or rolled, without tearing or shelling, but strips can be torn by hand when a smaller piece is needed, without compromising the sanding surface.
Aluminum oxide is a popular choice among industrial professionals because of its fast cut-rate and long life. This mineral makes a tough, durable abrasive that self-fractures to expose fresh cutting edges, whereas traditional natural abrasives dull more quickly. Aluminum oxide is suitable for a wide variety of materials in both woodworking and metalworking, including ferrous alloys. Aluminum oxide abrasive can be used on ferrous and non-ferrous metals, wood, and plastic.

3M 35826, Hookit Dust Extraction Flexible Sanding Block, 178 mm x 67 mm, 7100256500
Dynabrade 40320 Dynafile II Abrasive Belt Tool
Dynabrade 14010 Dynafile Abrasive Belt Tool Versatility Kit
Dynabrade 14360 Pneumatic Pipe Belt Finisher
3M 49054, Polyurethane Sealant 540, White, 310 mL Cartridge, 7000000941, 12/Case
Dynabrade 40610 Electric Dynafile II Abrasive Belt Tool
3M 19764, Utility Cloth Sheet 314D, 9 in x 11 in P320 J-weight, 7000000352 
