Feature:1. Adopt carburizing and quenching process, high surface hardness and high wear resistance 2. Flexible clamping with three jaws for greater clamping range 3. Suitable for holding drill bits between 1-16 which is stable and firm 4. Simple structure, convenient to load and unload, and longer service life 5. Can maintain the toughness of the core after low-carbon quenching, so that the tool holder can withstand a certain impact and load Specification:Item Type: Drill Chuck Tool HolderMaterial: High speed steel Model: BT40-APU16-100 Applicable Machine Tools: CNC, CNC milling machine, high speed machine Processing Range: APU Hardness: HRC56 Clamping: 1-16 Carburizing and Quenching Hardness: HRC56 Carburizing Depth: 0.8mm Package List:1 x Drill Chuck Tool Holder