This is a Multi-Purpose Rail. Really Right Stuff makes Multi-Purpose Rails in a variety of lengths, from 73mm to 192mm (2.4-inches to 7.6-inches).
- Use as a lens plate for a collared lens.
- Use as a camera body plate for some medium and large format cameras.
- Add a clamp to the rail and use use as a nodal slide for panorama photography.
- Attach to the bottom of any object to mount in a Really Right Stuff clamp.
- As of May 2012 this rail replaces the legacy B97 lens plate.