Keyring with car and house keys, brass tag

I lost my black leather keyring with a brass dog-tag key fob yesterday around 3pm near the Liberty Bell Center on Market Street in Philadelphia. It has two silver keys—one for my apartment and one for my car—and a small red USB drive attached. The brass tag has a tiny dent and the leather is scuffed, but the whole thing is still sturdy. This item is sentimental to me—it's a gift from my mom and I'm really hoping to get it back.