The mini chuck is made of high-quality metal material, which is wear-resistant and durable. The keyless mini chuck can hold tools with a shank diameter of 0.3-3.4mm, such as drill bits, for drilling, polishing, and grinding. The keyless mini chuck is designed with a non-slip texture, and the mini chuck can be easily tightened by hand. The hole diameter of the brass connecting rod of the keyless mini chuck is different, and it can be installed on the motor shaft according to the corresponding diameter. The mini drill chuck is compatible with most rotary tools such as micro drills, grinders, etc. Can be easily tightened by hand. Product Description Feature: 1. Made of high quality metal, wear-resistant and durable. 2. The chuck can hold tools such as drill bits with a shank diameter of 0.3-3.4mm for drilling, polishing, grinding, etc. 3. The chuck adopts a non-slip texture design, which is convenient to tighten by hand. 4. The brass connecting rods have different openings, which can be installed on the motor shaft with the corresponding diameter. 5. Compatible with most rotary tools, such as miniature electric drills, electric grinders, etc. Specification: Material: Brass + Aluminum Alloy Clamping Range: 0.3-3.4mm Outer Diameter: 10mm Installation Hole Diameter: 3.17mm Package Weight: 25g (Approx.) Packing List: 1 x Chuck 1 x Connecting Rod 1 x Hex Wrench