An auxiliary switch for a circuit breaker of the split case type. The switch is capable of switching the rated interrupt current capacity of the breaker and is fitted in to the circuit breaker case so that the overall width is substantially equal to or less than the overall width of the circuit breaker. Several embodiments of the auxiliary switch disclose various features which contribute to increasing the interrupt current rating and/or down sizing the width of the auxiliary switch. Among them are: an early make, late break of the auxiliary contacts compared to the circuit breaker contacts; an inertia dampening fly wheel attached to the actuator of the switch to enhance the early make/late break feature; a wiping action between the moveable and stationary contacts of the auxiliary switch to clean off welding and debris deposited from arcing; dual auxiliary contacts to enhance the contact area with little impact on package size and width; and a positioning of the auxiliary actuator on the contact lever of the circuit breaker to prevent the spring forces acting on the actuator from affecting circuit breaker contact pressure.