3M™ Disc Pad Face Plate backs a same size fiber disc (sold separately) to provide firm support and the force required for grinding applications. It is used in conjunction with a disc pad hub (sold separately), which attaches to the power tool, and held into place along with the appropriate disc using a retainer nut (sold separately). This assembly allows 3M™ Disc Pad Face Plate to be easily changed without removing the disc pad hub, allowing the operator to use a single tool for multiple applications from heavy grinding to finishing a workpiece. Some face plates have ribbing ...