Feature:1. The focus ring is the best choice for magnifying or altering lenses. It provides a focusing system for lenses without a focusing system.2. It can also be used as a macro tube to provide fine focus control for macro photography.3. Support 2555mm/12.2in focusing range, provides a 30mm/1.2in adjustable distance for lens focusing.4. Made of high quality aluminium alloy material, black anodized for longer service life and excellent hand feel.5. Extinction treatment on the inner side to avoid reflections affecting imaging.6. Adopted M58 helicoid interface is universal and easy to transfer, make the idle old lens can also be used for digital camera shooting.Specification:Condition: 100% brand newItem type: Focusing Helicoid AdapterMaterial: Aluminium AlloyColor: BlackWeight: Approx. 111g/3.9ozFocusing Range: Approx. 2555mm/12.2inInterface: Male Mount: M58 Helicoid MountFemale Mount: M58 Helicoid Mount.Package List:1 xFocusing Helicoid Adapter