Durable copolymer backing is impregnated with a tough aluminum oxide abrasive grainNo need for a back-up padUnique self-trimming designEasy contour grinding TRIMMING INSTRUCTIONS:When abrading with Trim-Kut, the outer surface of the disc is normally the first to become dull and lose its cutting action. To maximize the value of Trim-Kut, the dulled periphery may be trimmed off by the following unique method. Be sure to adhere to all instructions regarding personal protective equipment and equipment precaution requirements when trimming a disc. Operate the grinder with the back surface of the disc inclined approximately 5-15° against a secured piece of scrap metal or ceramic. By exerting a slight amount of pressure (towards the operator) the custom thermoplastic material will dress down to the desired new diameter. High RPM and a sharp edge of scrap will result in quicker trimming action. Disc may also be trimmed using a scribe or sheers.