Central Pnuematics 3" die grinder/air cutter (#47077) tool is a fantastic addition to any toolbox. With variable speed control, rear exhaust and speeds up to 18,000 RPM, this air cutter tool helps cut through metal quickly and safely. The Harbor Freight die grinder tool requires 90 PSI, and at least 5.5 CFM. Don't forget to order your selection of metal cutting wheels. You should also check out our great selection of air compressors as well.