. R8 Holding all ER16 collets. Clamping from 1mm-10mm. Straight type extended handle, the handle body , applicable to deep hole processing, to extend the depth of processing needs. The nut can direct rotation tighten, high rigidity and strong clamping force. Color: silver and black material: metal Model: R8 ER20 Drawbar Thread: 7/16 inch Overall Length: 143mm (5.63 inch) diameter: 24mm (0.94 inch) Collet chuck Model: ER20 (Cap Hexagonal type) Maximum clamping: 10mm ( 0.39 inch) Run-Out Tolerance 0.01mm (0.0005 inch) Package included: 1 x Straight Collet Chuck Holder Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is 1-3cm. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.