It is a penumatic sander which widely used for auto repair, Jeans grinding, stone grinding. Description: Taiwan Original Movement,Long Service ... Use it, Hard Torsion High Quality, Widely used on Auto-Repair, Stone Grinding, Jeans Grinding Specification: Speed: 25000rpm Chuck size: 6mm ... 3mm(1/8") Chuck 1pc Penumatic Sander Air Sander Used For Jeans Grinding Auto Repair Stone Grinding