Available in the BT ER extension rod handle, can be used for clamping drill, milling Tool, straight shank tool. Performance stability, high accuracy durable and wear-resistant. Large holding force, wide clamping range. Spiral collets are widely used in boring, milling, drilling, tapping, grinding, and engraving, and so on. The correct methods of mounting the collet nut: Put the chuck into the pressure cap, gently turn the clamp spring, when eccentric portion of the pressure cap recessed clamp spring groove. Along the arrow direction and use equal force to push clamp spring, can mount pressure cap. Put the clamp spring and cap all together installed on the chuck body or spindle. Insert into the clamping hole after wipe the cylindrical shank, use a wrench to tighten the pressure cap, until clip firmly the tool before use. (Note: Avoid fastening pressure cap that not installed tool, to avoid damage the clamp spring) Use a wrench to loosen the pressure cap and took out the chuck or tool, remove the tool. Along the direction of the arrow push out the clamp spring. Then according to need replace other clamp spring. Material: 45 steel Type: ER32 Length: 40mm Diameter: 33mm Accuracy: 0.015MM Inner diameter: 2 /4 /6 /8 /10 /12 /16 /18 /20mm colour: Silver Package Contents: 9pcs * Collets Only 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.