Engineered for, this electric grinding features a stylish four jaw copper design that securely grips various drill bits, ensuring reliability during extended grinding and drilling operations Perfect for metalworking projects, jewelry polishing, wood carving tasks, and model making where consistent bit alignment and shaking release operations are critical This comprehensive 10 piece set includes multiple collet sizes ( 1 / 8 " to 1 / 4 ") with steel reinforcement collars, designed to withstand high speed applications up to 30, 000 while maintaining grip integrity Ideal for professional mechanics, enthusiasts, and workshop technicians requiring versatile solution for rotary tools, engraving machines, and bench grinders The brass constructed assembly keyless accessory replacement compatibility with multiple power tool attachments, featuring a auto centering mechanism for quick installation and enhanced tool stability, Manufacturer: JunsenF