I think this type of sliding charm does have an ambience in decor that resembles fobs, though believe they were made for bracelets or possibly necklaces.
The only question I had at first, was about the open-back. I think this type of back is rather unique. At first glance, I wondered if the bracelet once had a clasp in addition to the safety chain. Similar ones I've seen or owned before have had tongue in groove clasps or wide fold-overs. As long as the two ends are finished off properly to be a functional open-back, I assume it's an element of the design. But I still wonder how the two ends remain in place when worn.
