Thank you for viewing. This is the Nikon F-mount teleconverter, the AI AF-S TELECONVERTER TC-17E II 1.7×. The AF-S teleconverter is an attachment lens that, when mounted between an AF-S or AF-I lens, extends the focal length of the main lens by 1.7 times. It has good optical performance and allows you to fully utilize the performance of the main lens, resulting in excellent image quality. It also supports various signal transmissions from the main lens. ※The f-number becomes 1.5 stops darker. I was organizing my camera dehumidifier and found various items I wasn't using, so I'm putting them up for sale. It has been stored for a long time, so there may be minor scratches and dust, but they are not to the extent that they affect shooting. I don't see any mold. There is no box.