Unusual Antique Patinated Brass Watch Fob Chain - Hanna Pat Pend

I’m not exactly sure what this is, I’m guessing it’s some type of watch chain.

Brass Prince of Wales chain features a unique double hook clasp, the opposite end features a little swiveling lock (or whatever it is) that’s marked “Hanna Pat Pend” (see photos).

Approximately 19 ½” end-to-end.

Condition

Good. Minor wear and tear consistent with normal use and age. Dark patina on the brass. No major flaws to note.