Maxworks 60137 6-Inch Dual Action Air Disc Sander, 10,000 RPM Disk Size: 3-Inch; 4-1/2-Inch; 5-1/2-Inch 10,000 RPM No load speed; Built-in regulator for speed control Air Consumption: 4 CFM Maximum air pressure: 90 PSI; Standard 1/4-Inch air inlet Minimum hose size: 3/8-Inch diameter