Features High-Quality Material: Constructed from premium steel, ER11 collet chuck delivers durability and reliability for CNC milling tasks, ensuring long-term performance under rigorous industrial use. Precision Engineered: Spindle extension rod is precision ground to guarantee minimal unbalance, promoting enhanced safety and stability during high-speed cutting operations. Enhanced Depth: Featuring a straight extended shank, motor shaft extension allows for deep hole processing, accommodating the necessity to work with materials requiring precise deep cutting. Secure Clamping: ER11 collet chuck ensures an exceptionally powerful clamping force, due to its tightenable nut design, resulting in improved accuracy and reduced tool slippage. Versatile Applications: Ideal for a multitude of machining processes, including boring, milling, drilling, tapping and grinding, this inner 8mm collet chuck is a versatile addition to any CNC toolkit. Description: This collet is made of high quality steel for milling lathe tool and work-holding engraving machine. ER straight rod type collet extension handle body is relatively long, suitable for deep hole processing. The nut can be directly tightened to provide a powerful clamping force. This collet  can reduce costs, improve efficiency and would be a good replacement part for your old one. Features: This motor shaft collet is made of high quality steel material, straight shank with clamping nut to be tightened. Extension rod diameter and the other parts are precision ground to eliminate unbalance, increase safety when cutting. Straight extended shank fits for deep processing, meeting the needs of extending the depth of processing.  Collet is well packed in a protective container with label for safe transportation and storage. It is widely used in boring, milling, drilling, tapping, grinding and other processing. Specifications: Type: ER11A-8mm Material: Steel Height: 40mm / 1.57" Shaft Diameter: 16mm / 0.63" Shaft Inner Diameter: 8mm(±0.02mm) / 0.31" Nut Diameter: 19mm / 7.48" Nut Inner Diameter: 9mm / 3.54" Package Includes: 1 x Collet Note: Please allow 1-2mm error due to manual measurement. Thanks for your understanding. Package List