This is a mount adapter that allows you to use Sony E-mount lenses with autofocus on Nikon Z-mount cameras. I am selling it because I changed my camera system. - Purchased new in October 2025, used only a few times. I used a SIGMA 85mm f1.4 lens without any problems on a Nikon Zf. I have attached an image showing the current price on Amazon at the end. Thank you.