54mm to M77x0.75 (d=80mm) adapter (step-up ring) for Kowa 6mm lens

This adapter has two functions:

1. Allows using M77x0.75 filters on lenses with 54mm front outer diameter.
2. Allows coupling such lens with a matte box with 80mm opening.

This adapter is made for Kowa 6mm lens, but can mbe used with other lenses with similar front size.

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