Features Feature: 1. Vacuum quenching treatment: the collet is vacuum hardened, with high hardness, strong toughness, strong fatigue resistance, and can withstand certain impact and load 2. Integral structure: the mill tool holder is integrally formed, with good structural rigidity, the pressure is distributed to the precise needle roller of the cage during use, which is suitable for processing large cuts 3. Full Grinding: the shaft is fully ground as a whole, effectively protecting the connection of the cone bore of the drive head 4. Fine grinding process: the exterior is polished to a shine, beautiful and elegant, and the shank hole is finely ground, has high centering accuracy 5. Wear resistance and sturdy: the milling shank holder is made of high quality 40cr alloy steel, which has better wear resistance and more stable performance Specification: Item Type: Collet Chuck Tool Holder Material: 40cr alloy steel. Model: NT40 ER32. Rear drawing thread: M16. Rear opening: approx. 16 mm/0.6 inches. Structure type: monolithic. Accuracy: 0.003 Scope of application: CNC machining centers, engraving machines and other high speed machinery Package list: 1 x collet chuck tool holder. 1 x ER32 key. Package List 1 x Collet Chuck Tool Holder 1 x ER32 Wrench