Specifications:The extension rod made of high-quality materials, strong and durable.It can be used for automobile manufacturing, mold manufacturing, machinery manufacturing, etc.The extension rod can eliminate the dangerous of withdrawing the shank from the collet.Item Name: Extension RodMaterial: High Speed SteelFeatures: Durable, Engraving Machine Accessory, High StrengthModel:1/2" Handle Extension Rod, ER20-13 Collet (Included Collet)1/4" Handle Extension Rod, ER16-8 Collet (Included Collet)8mm Handle Extension Rod, ER16-8 Collet (Included Collet)Product Size: Length: 88mm/3.46", Diameter: 28mm-22mm/1.10"-0.87" (Approx.)Notes:Due to the light and screen setting difference, the item& 39;s color may be slightly different from the pictures.Please allow slight dimension difference due to different manual measurement.Package Includes:1 x Extension Rod (Included Collet)