M42-M42(36-90) M42 to M42 Mount Lens Focusing Helicoid Adapter Ring 36mm-90mm Macro Extension Tube

M42-M42(36-90) M42 to M42 Mount Lens Focusing Helicoid Adapter Ring 36mm-90mm Macro Extension Tube Features: Suitable for M42 mount lens without focusing ring. Can be used as a macro extension tube. No electronic element, manually controls aperture and focusing. Aluminum alloy material, CNC precision machining, durable and sturdy. Easy to install and simple to use. Specifications: Material: Aluminum Alloy Lens Compatibility: M42 screw mount lens Length: 17mm-31mm/ 25mm-55mm/ 36mm-90mm(optional) Packing List: 1 * Adapter Ring