This is an eyepiece correction lens for use with Nikon's round viewfinder. Please note that it cannot be attached to viewfinders with a square shape. This is a used item in usable condition, but because it is used, the rubber components have stretched, making it prone to falling off. There are no signs of mold or scratches on the lens surface. It is recommended for use with telephoto lenses. I used it for focusing in the center of the frame. The field of view is limited outside the center, making composition difficult. Shipping is planned via Nekopos (a Japanese delivery service).