Premium Material: Router bit adapter made of high quality steel, lightweight and flexible, wear-resistant and durable, high strength and high hardness. Excellent Performance: The collet chuck engraving has high-precision, tight and stable clamping, which can improve work efficiency. Standard Size: The router collet chuck has 3 different inner diameters, including 6mm, 6.35mm, 8mm. Wide Application: The router bit collet is suitable for engraving machine, trimming engraving machine, wood milling cutter, wood router, etc. Value Package: Comes with 6pcs milling cutter adapter in 3 different sizes, each size has 2pcs. Sufficient quantities and different sizes can meet your different demands. Feature: The milling cutter collet is made of high quality steel, good flexibility and stable performance, high strength and high hardness, wear resistance and durability. 3 different sizes collet adapter (6mm 6.35mm 8mm) can meet your various requirements in daily work. Specification: Material: Steel Model: 6mm, 6.35mm, 8mm Height: 2cm Color: Black + Silver Package Includes: 2 * 6mm Collet Adapter 2 * 6.35 Collet Adapter mm 2 * 8 mm collet adapter