The DeWALT DARB1G0605 4.5" 60 Grit High Performance Aluminum Oxide Fiber Resin Disc features a high performance aluminum oxide grain which allows the disc to break down quickly consistently exposing new grain for faster removal, with a proprietary material mix that ensures durable long life discs. A tough fiber backing prevents tearing. These 5/8"11 arbor discs use quick lock backing pads for quick disc changing. 5 disc package.