United Abrasives- SAIT 22015 Type 27 4-Inch x 1/8-Inch x 5/8-Inch Pipeline Long Life Specialty Grinding Wheels, 25-Pack A24R Pipeline - Long Life. Aluminum Oxide grain. For the pipeline industry. Designed and manufactured to perform both cutting and light grinding. Long Life. Ferrous metals (steel, cast iron, etc.) Only wheel designed for both cutting and light grinding, eliminating the need for 2 separate wheels General purpose formulation provides optimum performance over a wide range of applications All sizes reinforced with the highest quality fiberglass for maximum safety and performance Super-Lock Hub on all 5/8-11 threaded arbors in the safest, bibration-free design.