Side Mounted Headphone Holder

I have seen a lot of under-desk mounts for headphones and wanted something that wouldn't dangle under my desk where I keep bumping into them with my knees. So I made one that easily attaches to probably most bookcases. Easy print with no supports needed, the bolt goes into the main part and provides tension against the side of the bookcase. Easy peasy. If you worry about your bookcase, put a small piece of felt on the end of the bolt for protection. I haven't seen it make any marks, and since it's on the inside wouldn't be noticeable anyway but just in case you can add a piece of felt.