The chuck securely and tightly holds the drill bit, ensuring it does not easily loosen. Built to be durable with a long service life, it is ideal for extended periods of work. Installation and removal are straightforward, offering greater convenience and labor-saving benefits. The chuck accommodates a wide range of sizes from 2 to 13mm, making it suitable for various types of drills. The keyless and self-tightening design is more aligned with user-friendly technology. Specification: Features: The chuck provides a secure and firm grip on the drill bit, preventing it from loosening easily. Constructed for durability, it offers a long service life, perfect for continuous work. Easy to install and take apart, it offers enhanced convenience and saves labor. With a clamp size range of 2 to 13mm, it is compatible with many drill bit types. A keyless and self-tensioning design that better suits human technology needs. Technical Specifications: Diameter: 43mm (1.69 inches) Length: 58mm (2.28 inches) 3-5mm tolerance Connection Size: 1/2-20 UNF Clamp Range: 2 to 13mm (0.04 to 0.51 inch) Package Contents: 1 x Drill Chuck Note: Before making a purchase, please ensure that the connection thread of your electric drill is 1/2-20 UNF. (1/2 refers to the thread size, and 20 is the number of threads per inch. UNF stands for Unified National Fine, where UN is the standard codefor Unified National thread and F denotes a fine thread pitch).