3M Cubitron coated 777F PSA disc uses ceramic as the abrasive material and has a diameter of 12 in. 3M incorporates this ceramic material into the PSA disc forming a grit of 40. This abrasive is on a cloth backing, YF weight. All abrasive products that rotate or spin, such as the ones in this category, have a maximum speed at which you can run them. This 3M PSA disc can be run at a maximum speed of 2000 RPMs.