For the one other person in the world besides me who had never heard the word fob before. I think 2b is the one that applies.
fob
n.
1. A small pocket at the front waistline of a man's trousers or in the front of a vest, used especially to hold a watch.
2.
a. A short chain or ribbon attached to a pocket watch and worn hanging in front of the vest or waist.
b. An ornament or seal attached to such a chain or ribbon.