High Precision Spring Collets, Extensions, Adapters Holders and Retaining Studs for CNC Machines are made by Amana Tool, the leading manufacturers of cutting tools. All spring collets are inspected for quality & 100% accuracy. The high precision spring collets allow to reduce the vibrations on the tools and motors, assure better results and prolong the life of the tools and electrospindles. Using Amana Tool UHO-50 Universal Adjustable Auto-Locking Stand for ISO30 Tool Holders with 50mm Flange results in the very best tool performance. SPECIFICATIONS: (D) Diameter: 50mm; Description: For ISO30 Tool Holders with 50mm Flange; Fits Tool No.: HO-112 and HO-116.