A circuit breaker is an automatically-operated electrical switch designed to protect an electrical circuit from damage caused by overload or short circuit. Unlike a fuse, which operates once and then has to be replaced, a circuit breaker can be reset (either manually or automatically) to resume normal operation. Circuit breakers are made in varying sizes, and types. Wirthco Engineering has blade style and three stud mounted styles plus manual & switchable reset circuit breakers up to 200 amp.