These spring collets are made of high-quality 65Mn spring steel for use with CNC milling lathe tools and work-holding engraving machines. The set includes 14 collets of various sizes to meet basic needs. Each collet is individually packed in a protective container with a label for easy identification. The collet must be placed into the collet chuck nut before inserting into the collet chuck. Features: - Made of high-quality spring steel for stable performance - Fine workmanship, good elasticity, and high precision - Each collet is individually packed in a labeled protective container - Compatible with CNC milling lathe tools and work-holding engraving machines Specifications: - Material: 65Mn spring steel - Model: ER20 - Size Range: 1/16", 3/32", 1/8", 5/32", 3/16", 7/32", 1/4", 9/32", 5/16", 11/32", 3/8", 13/32", 7/16", 1/2" - Height: 30mm / 1.18" - Outer Diameter: 21mm / 0.82" - Run-Out Tolerance: <0.008mm - Weight: 550g (approx.) Package Includes: 1 Set (14 pcs) x Collets Note: - Please allow 1-2mm error due to manual measurement. - Monitors are not calibrated the same; color may vary slightly from the actual product. Please refer to the physical item for accurate color.