3M(TM) Hookit(TM) Low Profile Finishing Disc Pad 16459, 5 in x 11/16 in 5/16-24 External, 10 per case Designed for use with 5 inch Hookit(TM) discs. Pad is made with a soft density foam for better conformability and allows the disc to flex which gives longer abrasive life in loading applications. 5/16 in-24 EXT thread. MOS: 12,000 RPM/OPM.