This is a brass key ring I purchased at a used clothing store about 10 years ago. It uses a flathead screwdriver to loosen a screw, allowing you to insert keys between the rubber gaskets and then tighten the screw to secure them. When in use, you can rotate only the necessary key out, and when storing, you can rotate the key 180 degrees for compact carrying. It has some signs of use, but is in good condition. Thank you very much for looking.