A circuit breaker assembly 10 includes a plurality of circuit breakers 12, 14 each including a housing 16, 18 with a trip mechanism therein and each having an opening 32 in a side of the respective housing. Each trip mechanism has a coupler disc 24 connected thereto. The plurality of circuit breakers are aligned in an end-to-end fashion with a trip member 21 positioned along a side of the housings and connected to the coupler discs 24 such that if the first trip mechanism actuates from a untripped state to a tripped state the trip member 21 actuates the second trip mechanism from a untripped state to a tripped state and vice versa.