Atoplee 1/8 inch and 1/4 inch Er11 Spring Collet Set for CNC Engraving Machine & Milling Lathe Tools Material: 65Mn MODEL: ER11 1/8''; ER11 1/4" Length:17.7mm Precision:less than 0.012; Height:0.69'', Outside diameter: 0.45'' (11mm) Package Included: 2pcs CNC ER11 Collet 2pcs 1/8 inch and 1/4 inch Er11 Spring Collet Set Good elasticity, high precision Using high quality spring steel is table in perfomance For CNC milling Lathe Tool &amp; Workholding Engraving machine MODEL: ER11 1/8&#039;&#039;; ER11 1/4&#034; Length:17.7mm Precision:less than 0.012 Height:0.69&#039;&#039; Outside diameter: 0.45&#039;&#039;(11mm) Package Included: 2pcs CNC ER11 Collet