Features: Strong and stable copper collet chucks designed for accuracy gripping and long lasting performances in demanding rotary tool applications, featuring a polished brass layer for enhanced erosion resistance. Engineered with a bright copper plated cores and standardized 4.8mm (0.19") inner diameter compatibility, this power tool accessory seamlessly integrates with drills, electric grinders, and hose mounted polishing systems. Ideal for professional mechanics, enthusiasts, and woodworking specialists requiring secure bit retention for high speed rotary tools in workshops or home garages. Perfect for metal fabrication projects, accuracy carving tasks, automotive maintenance, and industrial grade polishing operations where shaking control and tool stability are critical. Optimized for reduced slippage during extended use, this copper collet chucks ensures consistent transmission while maintaining compatibility with general rotary tool accessories across multiple brands. Specifications: Component : Brass Size: Direct clamping of clamping end: 4.3mm/4.8mm Package Includes: 10/11xElectric Grinding chucks note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item.