Cratex® Rubberized Abrasives are made with oil-resistant chemical rubber. In contrast to conventional grinding wheels, the Cratex® bond has unique cushioned action … cuts freely, smoothly and softly without gouging or digging into the work surface. It resists clogging or smearing, and is ideal for a broad range of applications where metallic or non metallic surfaces must be smoothed and polished without loss of dimensional tolerances or control.