Tubo de montaje macro adaptador de enfoque ajustable de latón M42 a M39 17 mm-31 mm
This adapter made with Copper core, high quality and stable. Firstly attach your M42 lens to this tube. The length of this Helicoid tube 17mm (min) to 31mm (max). M42 mount lenses. It will be better when you use it with filter adapter together.