This is a helicoid mount adapter for using Leica M-mount lenses on Sony E-mount cameras. The helicoid mechanism allows you to shorten the minimum focusing distance, enabling close-up photography. I purchased it for 27,000 yen along with a lens, but I am selling it because it did not suit my needs. It has only been used a few times and has no scratches. A warranty card is included to show that it is a recent purchase. Immediate purchase is welcome. Please consider it!