Description: M42 - M42 Thread DSLR Camera Lens Ring Adapter Macro Focus Tube 12mm to 17mm adjustable focal length. Connect some classic old lenses to modern popular cameras. Can be used as a lens without a focusing system after the lens is modified, or as a macro focus ring. The best choice for playing zoom lenses or modifying lenses. Specification: Material: Aluminum Size: 5.6x1.5 cm / 2.2x0.6 inch Package Includes: 1x Focus Adapter Ring
