3M Scotch-Brite non-woven SC-DH hook & loop disc uses aluminum oxide as the abrasive material and has a diameter of 7 in. Since this product is non-woven, Grade is generally used to describe the abrasiveness; with the 27679 having a very fine grade. 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 hook & loop disc can be run at a maximum speed of 6000.
From the Manufacturer
A non-woven abrasive product used for cleaning, finishing, blending and deburring applications. Contains a backing that mounts to hook and loop pads. Abrasive mineral: Very fine grade aluminum oxide.