Sell 【ra】M42 to M42 Focusing Helicoid Aluminum Alloy Macro Extension Tube 12-17mm best price

12mm-17mm M42 to M42 Adjustable Focusing Helicoid Adapter Aluminum Alloy 42mm Macro Extension Tube 5mm Max Movement  Feature:  Very useful for lenses without focus ring. It could be used as macro barrel, and offers fine focus control for macro photography. NO electronic element in the adapter, aperture and focusing must be manually control. Specification: Material: aluminium alloy Lens compatibility: for M42 mount lens Length: 12mm to 17mm (5mm movement distance for focusing) Focus: manually Note: 1. There may be slight size deviations due to manual measurement, different measuring methods and tools. 2. The picture may not reflect the actual color of the item because of different photographing light, angle and display monitor. Included: 1 X Focusing Helicoid