This is the new version Lens Ring for Samyang 8mm F2.8 Fisheye I and II (Sony E-Mount). New design allows full access to focus and aperture rings on the lens.
Note to users of shaved original Samyang 8mm f/2.8 Fisheye I on full frame sensor cameras. LRP45 causes a larger nadir footprint when mounted on R1/10/20, even though the image quality is not very good at the extreme edge. Customers can ask for swapping it with LRP40 OR just use LRP45 and take a nadir shot for better image quality.
How to Mount a Lens Ring onto the R Series Panorama Tripod Heads