Cloth Abrasive Backing—Resist tearing and hold up to wet sanding better than paper-backed discs.

Paper Abrasive Backing—Good for high-volume sanding where you'll go through lots of discs.

Silicon Carbide Abrasive—The best choice for sanding concrete floors. You can also use them on wood floors, but they’ll wear out quicker than ceramic alumina discs.

Ceramic Alumina Abrasive—The best choice for sanding wood floors, and no risk of color transfer. They won’t dull as fast as silicon carbide discs because their grit particles continuously fracture to create fresh, sharp cutting edges. However, they are not sharp enough to sand concrete floors.

Grit—The lower the grit number, the rougher the finish and the duller the appearance. The higher the grit number, the more polished the finish and the more satin or mirrored the appearance.