Circuit breakers protect the wires in your home from overheating (referred to as an overload) and fault currents (referred to as short circuits). The Eaton Cutler-Hammer 20/20 amp 1 inch duplex type BR circuit breaker is also known as tandem breaker. Tandem breakers are convenient for adding circuits to a full load center and are sometimes used to reduce the physical size of the load center. This a non-circuit limiting breaker. The BR tandem line of breakers is intended for replacement purposes on load centers made prior to 1968.