Features: 3.Adopt high quality spring steel material,good flexibility and wear resistance.4.High precision ,tight and stable clamping, extra long life, good flexibility and resistance to abrasion.5.Work with 6mm Collet ,such as drills ,engraver, reamer etc.Help to adjust the shank of the CNC engraving bits from 6mm to 3.175mm.Specifications:Material: Tungsten steel Color: SilverBrand name: BQLZRSize: Total length: 24mmDiameter(Outer): 6mmDiameter(Inner): 3.175mmWeight: 24gPackage include:8 x CNC Router Tool Adapters Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Sold by-YJL official store