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 72600, 663FC 1/2" X 30", 70u Diamond Trizact Belt, 7100206529
Dynabrade 95674 1/4" Female Coupler
3M 77197, Scotch-Brite™ Roloc™ Deburr and Finish PRO Unitized Wheel,TR, 3 in x 1/8 in x NH, 8C CRS+, 7100109130, 40/box
Dynabrade 78600 3/8" Dia. x 2" W x 1/8" Center Hole, 120 Grit, 100/pack
3M 20279, Disc Pad Holder 947TH, 7 in x 1 in x 5/8-11 Internal Black T Hook, 7000118602
3M 19766, Utility Cloth Sheet 314D, 9 in x 11 in P240 J-weight, 7000000354 
