Art-Snaps are magnets made to put on your mailbox or steel door. You can get them with numbers (the ones with a blank spot) or with wording such as Welcome Friends (picture shows wording).Â These are packaged individually. If you need one for each side of your box, please purchase 2. These are great for any size mailbox, standard or oversized. They fit behind the postal flag so no slot is necessary. These art-snaps are 5.5" high by 15" wide.