DEWALT DW4436 4-Inch by 5/8-Inch 80-Grit Fiber Disc 25Pcs. Technical Details High performance aluminum oxide grain allows the disc to break down quickly consistently exposing new grain for faster removal Proprietary material mix ensures durable long life discs Tough fiber backing prevents tearing 5/8-inch 11 arbor discs use quick lock backing pads for quick disc changing 25 Pack