Griton's Quick Change Sanding Discs are converted from a new range of high performance surface conditioning materials that allow you to get your desired finish quicker and better. These new materials offer a wider range of grade and finer finishes than conventional materials. Designed with premium grade Aluminum Oxide coated on a heavy fiber back to withstand high heat and water resistant.  Available in three different types of mounting:  T1: Push-on,  T2: Screw-on and T3: Roll-on hub.