Blue Sea Systems 2-Position/2-Pole Lockout Slide Allows only 1 double pole AC circuit breaker to be activated at a time Guarantees that AC power from 2 or 3 sources (shore power and genset or inverter) will not be mixed Fits all World or A-Series and Rocker double pole circuit breakers Uses circuit breaker mounting screw holes; Requires no special panel modification Includes mounting screws