Specifications: Chassis size: 2 inches or 3 inches Air inlet size：1/4 inch Hose size: 3/8 inch Deflection diameter: 3mm Maximum speed: 15000rpm Air consumption: 4CF Air pressure: 90psi Package Include: Air sander, 12 Pcs 2inch Polishing Buffing Sponge, 3 pcs Wool Pads, 12 pcs 3inch Polishing Buffing Sponge 3 pcs Wool Pads1 pcs 2 inch Backing Plates,1 pc 3 inch Backing Plates,60 Pcs Sandpapers,1 pc thimble 94 in total. Refueling Tips: 1. This machine is highly accurate. When it is running, the Speed is high. Once any fine sand or iron filings enter the movement, it may cause the blade to break and cause the machine to malfunction, so make sure that the air inlet is clean. 2. Be sure to use an oil-water separator and drain regularly to make sure that the machine is dry. 3. Before use every day, be sure to add 3~5 drops of pneumatic oil to the air inlet of the machine, and connect the air pump to idle. 4.Before use, the sponge pad should be cleaned and dried in the shade to achieve the best results before use