This ER collet is used for CNC milling lathe tools and work holding engraving machines.Collet must be placed into collet chuck nut before inserting into collet chuck.Specifications:Model: ER20Clamping Diameter: 1/2-inchMaterial: 40Cr SteelPrecision: 0.015mm / 0.0006-inchTotal Height: 31.5mm / 1.24-inchOuter Diameter(Max): 21mm / 0.83-inchPackage Includes: 2pcs x Spring Collet.
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