Feature: 1. APPLICABLE SCENARIO: ERG16 collet is suitable for clamping grinding heads on various grinding machines, suitable for repairing and grinding tires. Compatible with most rotating tools used in hardware, hobbies, home, and more. Widely used in machining centers, ordinary grinding machines, CNC grinding machines, engraving machines, high speed machines, and other processing. 2. SPRING STEEL MATERIAL: These spring collets are made of spring steel, which is sturdy, durable, stable in performance, and convenient. 3. FINE WORKMANSHIP: Collets are completely hardened, very durable and sturdy, suitable for your long term use. 4. STABLE OPERATION: Collet chuck has undergone accuracy grinding with a total runout of less than 0.0003. 5. HIGH USABILITY: Very suitable for various machining applications, including boring, milling, reaming, tapping, and grinding. Specification: Item Type: Collet Chuck Material: Spring Steel Barrel Specification: d=10 x 8; D=9 x 7.1; D=9 x 7; D=8 x 6.3 . Package List: 4 x Collet Chuck4 x Storage Cartridge