An interface or throttle control assembly includes a housing and first and second wheel rotatably supported by the housing adjacent to each other. The assembly also includes a pair of tabs, each projecting from a corresponding one of the wheels. The tabs are engagable with each other. The assembly also includes a latch mechanism which mounted on one of the wheels. The latch mechanism is movable to a latched position engaging the other wheel so that the wheels rotate together, and is movable to an unlatched position so that the wheels can be rotated independently of each other.