This item has been stored unopened since it was purchased new. I am selling it because I have no use for it. This adapter allows you to mount Voigtländer VM and ZEISS ZM lenses on Nikon Z mount mirrorless cameras and focus from infinity. The 5.5mm helical focusing mechanism allows you to get "even closer" than the lens's minimum focusing distance. It can also be used with the M bayonet adapter ring previously sold by our company to mount Voigtländer/L mount interchangeable lenses.