I believe that F.M.B.A. (Firemen's Mutual Benefit Association) actually was a form of insurance. My son is a volunteer firefighter and was told that in the early years fire departments (usually volunteer) sold insurance at a nominal fee for fire protection. As I understand it, that was the way fire departments were able to maintain their equipment. Each insurer was given a cast iron sign which was then attached on or near the front door. Bunny in CA