A Pneumatic Air Die Grinder Kit is a compressed air–powered tool set used for grinding, polishing, shaping, and deburring metal, wood, or plastic surfaces. Specifications -Type: Straight or Angle Die Grinder -Collet Size: 1/4" (6mm) or 1/8" (3mm) -Free Speed: 20,000–25,000 RPM -Air Inlet: 1/4" NPT -Air Pressure: 90 PSI (6.3 bar) -Air Consumption: 4–6 CFM -Body Material: Aluminium alloy -Included accessories: Grinding stones, collets, wrenches, oil bottles, carry case - Use: Grinding, deburring, polishing, and finishing applications