This is the Pentax "Mount Adapter K". I purchased it to use M42 screw mount lenses, but it has been stored unused. Current models seem to be stamped "Philippines" instead of "Japan". There appears to be a faint pattern on the surface. It may be marks from the outer bag adhering during storage. Please check the fourth image. Returns are not accepted, so please confirm any concerns beforehand. I hope those who understand that this is a home-stored item will consider purchasing it.