You do not need to use chunk key or pin or wrench. Just a momentary interruption in your work. There have got a level mechanism on the handpiece body. It can help you open it quickly and smoothly.<br> This item also with the features of low vibration and slowly heating when working.<br> Suitable for grinding, drill, mill and other supporting use, Adopting high quality metal material, smooth surface.<br> Cabinet and delicate and comfortable using.<br> Common used in processing of Jewelry and crafts.<br> Colour: silver + black<br> Material: metal<br> Length: 14.2 cm<br> Collet : 2.35 mm<br> Package Contents:<br> 1 * Flex Shaft Machine<br> Only the above package content, other products are not included.<br> 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.