M12 thread milling shank chuck high accuracy collet chuck for CNC lathe Feature:1. Vacuum quenched: the collet holder has been vacuum quenched, it has high hardness, high strength, good fatigue, impact resistance and load resistance2. Good structural rigidity: the milling mandrel holder is integrated, has good structural rigidity, the pressure is distributed to the high-precision cylindrical needle roller cages during use, suitable for processing large quantities of cutting3. Protective connection: the collet holder is fully grounded as a whole, effectively protecting the conical hole connection of the power head4. Grinding processed: the outside of the chuck is brightly sanded to achieve a beautiful and elegant appearance, mandrel hole grinding is processed, with high centering accuracy5. Wear resistance and stability: the milling tool holder is made of high-quality 40cr alloy steel, it has better wear resistance and good stabilitySpecification:Item type: cutter holderMaterial: 40cr alloy steelModel: NT30 ER20Back drawing thread: M12Tail aperture: about 12mm/0.5 inchStructure type: monolithic, You can mention them: 0.003Scope of application: CNC machining centers, engraving machines and other high-speed machinesPacking List:1 xMilling Shank Chuck for 1 x ER20A wrench