737U | 4.528″ x 13-1/8′ | Grit 320+ Features 3M Precision-Shaped Grain, triangular-shaped grains that cut at least 30% faster and last at least 30% longer than other conventional ceramic abrasives. Clean Sanding multi-hole pattern delivers excellent dust extraction. 3M Hookit hook-and-loop attachment makes for fast disc change-outs. Kiss-cut scoring technology allows for use in multiple sheet lengths. Sharper cutting surface means less pressure is required. Grains are electrostatically oriented on the abrasive surface for efficient cut.