3M(TM) Hookit(TM) Clean Sanding Low Profile Disc Pad 20356, Hook and Loop Attachment, 6" Diameter x 3/8" Thick, 5/16"-24 External Thread, 52 Holes, Red  (Pack of 1) Clean sanding low profile disc pad Attach with 6 inches diameter Hookit(TM) clean sanding discs or Hookit(TM) D/F discs Use with random orbital sanders with 5/16 inch-24 internal threads Made with red foam 5/16"-24 thread size