42" Extension Flexible Rotary Drill Tool Drive Flex Shaft Attachment Features Convenient and easy to operate, it is widely applied in electric grinder, drill, engrave, polish and mill. Easy attaches to rotary tool in seconds, electric grinder with flex shaft, easy to reach hard-to-reach pipes, interfaces, corners, etc. Specifications Material: Rubber Size: approx. 41.73"(106cm) Thread: M18x1.5 Suitable for M18-M19 thread Thread Pitch: 1.5mm Axis Diameter: 3.2mm Suitable Clip Head: 8x0.75 How to Connect the Flex Shaft and Machine: 1.Remove rotary tool collet nut, rotary top cap. 2.Slide collet nut onto shaft core and insert shaft core into collet. 3.Tighten collet nut to make sure the shaft core is tighten. 4.Screw shaft connector onto the rotary tool. Package Included One (1) Extension Drill Shaft L Key