A circuit breaker having a shunting contact structure with low watts loss and high withstand level. The circuit breaker of the present invention comprises an upper contact arm having a first contact disposed thereon and a lower contact arm having second and third contacts thereon with the second contact mating with the first contact. A shunt terminal is provided between the upper contact arm and the lower contact arm. The shunt terminal includes a fourth contact which mates with the third contact on the lower contact arm. The circuit breaker of the current invention has a closed, open and current limiting position. When the circuit breaker is conducting nominal rated current, the first, second, third and fourth contacts remain closed. When the circuit breaker is under fault conditions which are circuit current conditions above the withstand level, the circuit breaker switches to a current limiting mode. In this mode, the upper contact arm and the lower contact arm move simultaneously in an upward and downward manner respectively, thereby opening the third and fourth contacts resulting in a blow open loop that opens the first and second contacts and protect a load coupled to the device from overcurrent conditions.