Ultra Precision ER Spring Collets for Collet Chuck/Holder, T.I.R. 0.0001″ – 0.0002″, Clamping range is 0.020″ – 0.039″, Made out of High Quality steel, 100% Quality control in the USAHIGHEST ACCURACY: Ultra Precision Spring Collets 0.0001″-0.0002″ T.I.R.WIDE CLAMPING RANGE: Clamping Range 0.02″-0.039″ Depending on Diameter.PRECISION CLAMPING FORCE: Provides Maximum Clamping force around tool with Precision Collapsability.HIGH QUALITY STEEL: Made of High Quality Case Hardened Steel for long lasting operating life and elasticity of Collet.QUALITY CONTROL PROCESS: Hand Inspected and Run out Tested 100% Customer Satisfaction Guarantee.High Quality SteelChinaManufacturer100% Guarantee to be Free from any Manufacturing Defects. 100% Customer Satisfaction Guarantee