This is a wide lens panel or lens board for X-Act2 that mounts to the rear side of the front standard which enables wider lenses to be used with more movements. It has an integral cone shaped soft leather bellows that attaches to the rear standard. This lens panel is ideally suited for lenses 35mm to 60mm though but may fit wider lenses too.
This is used, but condition is excellent. Leather is still very supple. Minor cosmetic crud on connection pin which obviously won't affect anything in use.
These are very rare and hard to find! And I have two of them currently!