Roloc Disc Pad Assembly, 05538, 1 in. Backup pad designed to support 3M Roloc 1 inch diameter abrasive discs. This pad has a 1/4-20 INT thread which allows it to be mounted directly to tools with 1/4-20 EXT threaded shafts. Assembly also includes a Roloc shank and adaptor. Max operating speed: 30,000.