Features [Main application] This cnc engraving machine collet is used for CNC milling machine turning tool and workpiece clamping engraving machine [High-quality material] The spring collet is made of high-quality spring steel with stable performance [Individual packaging] Each collet is packed in a separate protective container with a label [Fine workmanship] The workholding engraving collet has fine workmanship, good flexibility and high precision [Caution before use] The chuck must be inserted into the chuck nut Description: These spring collets are made of high quality 65Mn spring steel for CNC milling lathe tool and work-holding engraving machine. There are total 15 collets of various sizes in on set which can basic meet your need. Each collet is well packed in separate protective container with label so you can easily distinguish them. Collet must be placed into collet chuck nut before inserting into collet chuck. Specifications : Material: 65Mn spring steel Model: ER20 Range: 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm Height: 30mm / 1.18" OD: 20mm / 0.78" Run-Out Tolerance: <0.008mm Weight: 585g(approx.) Package Includes : 1 Set(15pcs) x Collets Note: 1. Please allow 1-2mm error due to manual measurement. Thanks for your understanding. 2. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard. Package List