High Quality: High-carbon steel,Micro-Drill Chuck Key 0.3-4mm JTO Taper Mounted Lathe Chuck Mini Drill PressMini Drill Chuck Key 0.3-4mm Mounted Lathe Chuck Pcb Mini Drill Press Applicable To Motor Shaft ConnectingKey Type Electric Hand Drill Chucks Cap 0.3-4mm JTO Taper Mount Lathe Chuck PCB Drill Press Hobby Model ToolsHigh precision screw thread and tapered hole.Compatible with impact dril and different power electric drill.Application: Compatible with impact dril and different power electric drill. Also fits 3.17mm shaft motor. For milling machine, lathe, drilling machine, wood working machine.Type: JT0 taper the biggest end of diameter: 6.350mm JT0 taper The smallest end of diameter: 5.800mm Outer diameter: 21.5mm Taper: 2 degrees 49 minutes 24.7 secondsclamping range: 0.3mm-4mm( 0.01inch - 0.16inch) Drill,The maximum clamping 4.2mm. Connection size: JT0 (inner hole diameter is 6 mm) fit motor / machine shaft diameter : 3.17mm include: 1 x 0.3-4mm Drill Chuck 1 x 3.17mm Drill shaft 1 x drill keycolour: silverMaterial: MetalPackage Contents:1 set x micro-drill chuckOnly 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.