Features: *100% brand new and high quality *Made of high-quality materials, durable *Special chuck for woodworking trimming machine *Material: Carbon steel *Inner hole diameter: 6mm or 6.35mm (1/4" ) *Model: AR-6 or AR-1/4 (6.35) packing list : 1*Chuck (6mm or 6.35mm) Note: 1. The real color of the item may be slightly different from the pictures shown on website caused by many factors such as brightness of your monitor and light brightness. 2. Please allow slight manual measurement deviation for the data.