4-piece router bit collet adapter set with sizes 12-6 mm, 12-10 mm, 7-6 mm, and additional sizes for broad compatibility. Compatible with a wide range of routers and bit tools. Carbon steel construction provides durability and wear resistance for long-term use across varied applications. Precise clamping force delivers a stable grip, keeping bits securely in place during operation and improving cutting efficiency. Wide compatibility with different bit-tool and chuck specifications; ideal for professional and DIY projects needing diverse machining setups. Use scenarios: - Adapt a bit with one shank to a router chuck that requires a different size, great for cabinet making and furniture work. - Route edges, grooves, and dadoes in wood, plastics, or soft materials using various bit shanks. - Perform engraving or decorative routing with reliable bit retention and accuracy across multiple tools.