• Front side - M77x0.75 female thread with 80mm outer diameter
• Rear side - M52x0.75 male thread

This adapter has two functions:

1. Allows using M77x0.75 filters on lenses with M52x0.75 filter thread.
2. Allows coupling such lens with a matte box with 80mm opening.
3. There is M49x0.75 female thread in the rear part, so you can use it to mount a polarizing screw-in 49mm filter there and add other 77mm filter to the front.

This adapter is made for LOMO Foton zoom lens, but it will fit any other lens with 52mm filter thread.

Made of anodized aluminium. Front 80 mm snap-on plastic cap is included.