3M™ Disc Pad Face Plate 81734 is an extra-hard, ribbed plate for use with 5 inch diameter x 7/8 inch 3M™ Fibre Discs and 2 1/2 in 3M™ Disc Pad Hubs (sold separately). 3M™ Disc Pad Face Plates back a same size fibre disc (sold separately) to provide firm support and the force required for grinding applications. The plate attaches to the power tool and is held in place along with the appropriate disc using either a retainer nut (sold separately) or TN or GL quick change attachment systems. The ribbed bottom provides additional force when needed for optimal fracturing of the abrasive mineral, and helps increase the grinding pressure of the abrasive with the same amount of operator effort.