Features Spring band made of high quality spring steel, they are performance stable. Fine workmanship, good elasticity, high precision. The collet must be inserted into the collet nut before inserting into the collet chuck. Each collet is packaged in a separate protective container with label. For CNC router tool and engraving machine. Description: These collets are made of high-quality 65Mn spring steel for CNC milling tools and engraving machines. There are a total of 6 collets in different sizes in the set that can meet your basic needs. Each collet is well packaged in a separate protective container with label so you can easily distinguish them. The collet must be inserted into the collet nut before inserting into the collet chuck. Features: Spring band made of high quality spring steel, they are performance stable. Fine workmanship, good elasticity, high precision. The collet must be inserted into the collet nut before inserting into the collet chuck. Each collet is packaged in a separate protective container with label. For CNC router tool and engraving machine. Specifications: Material: 65Mn spring steel. Model: ER32 Range: 10mm, 12mm, 14mm, 16mm, 18mm, 20mm Height: 40 mm. Outer diameter: 31 mm. Concentricity tolerance: <0.008 mm. Weight: 753g (approx.) Package includes: 1 set (6 pieces) x collets. Note: 1. Please allow 1-2 mm error due to manual measurement. Thank you for your understanding. 2. Monitors are calibrated differently. The object colour shown in the photos may differ slightly from the actual object. Please take the real one as standard. Package List