set2: 3 x ER20 Spring Collet + 1 x Collet NutsProduct Name : Collet Nuts;Model : ER20Hole Diameter : 16mm/ 0.6 inch;Thread Diameter : 25mm/1 inchOverall Size(Approx.) : 34 x 20mm/ 1.3 inch x 0.8 inch (D x L)Product selection of materials, high-quality spring steel long lastingWide range of applications, for example, boring, milling, drilling, tapping,engraving, CNC, and other processing.Suitable For: Boring, milling, drilling, tapping, engraving, CNC, spindle machines, and other processingThis collet nut is a great replacement for the broken part, fit most tool holders.Precision ground and hardened.This listing is only for 1 collet nut.SpecificationsMaterial: Spring steel/MetalColor: silver gray/BlackSize1/8:0.3cm1/4:0.6cm1/2:1.2cmHow to useInsert the tip into the pressure cap, gently turn the retainer until the pressure cap eccentric retainer portionrecessed groove along the direction of the arrow evenly push hard retainer, you can mount the internal pressure cap.The pressure cap with retainer mounted together on a spindle or chuck body, the cylindrical tool shank afterwiping loaded clamping hole, use a wrench to tighten the pressure cap even force until the date before the tool folder in prison use.(Note: not in the tool and avoid tightening pressure cap installed to avoid damage to the retainer)ATC with a wrench loosen pressure cap out of the chuck and the tool, remove the tool, retainer direction of the arrowpush hard to quit, and then need to put on retainer to the other aperture.Package Contents:3 x ER20 Spring Collet1 x Collet NutsOnly the above package content, other products are not included.Note: Light shooting 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.