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 72003, Powerflow High Efficiency SP3 Particulate Filter System Component 450-01-01R20, 7000131701, 20 EA/Case
3M 33446, Cubitron II File Belt, 80+, 1/2 in x 18 in (12.7 mm x 457.2 mm), 7100033186, 10 belts per carton, 5 cartons per case
3M 26053, PPS Series 2.0 Adapter, Type S14, 7/16 Male, 14 Thread UNC, 7100135932
Insize 4809, U.S. STAND SHEET METAL GAGE, 0-36(.3125~.0070"), 6928640330162
Dynabrade 53533 Cone or Plug Grinder (Triple Extension)
3M 71358, 641WY 1/4" X 24", 600 Mesh Diamond Cloth Belt, 7010534894
3M 19770, Utility Cloth Sheet 314D, 9 in x 11 in P120 J-weight, 7000000358
Norton 66261127733 - 2" X 50 Yard 60 Grit Metalite™ Aluminum Oxide Cloth Roll, 1 Each 
