High Precision ER COLLET DIN6499, also known as spring collet, is mounted on a drill \ milling machine, drilling and milling chuck, its function is to clamp drill cutter or knife. Er flexible collet is currently the most used. Its stable performance, high accuracy by the majority of manufacturers trust. All products are precision grinding, in line with the German DIN 6499 specifications precision manufacturing.High precision collet chuck combines advantages of DIN6499/ISO15488A standard and B standard. High speed cutting such spring collet is mainly applied to the need for good in the radial runout error.