3/4" by 1/4". Sterling Silver marked Sterling w Maker Mark. Like new condition.
St. Christopher was the patron saint for travelers. I say "was" because at some point the Catholic Church took away his sainthood. Growing up in a Catholic family, the girls would receive a St Christopher's charm to add to their charm bracelet when we received our driver's license. The boys would get these little statues that would attached to the dashboard of the car.
The charm shows St Christopher walking with a child upon his shoulder safely walking on a journey. Pretty much the universal symbol of St. Christopher.