Abstract: A pneumatic transfer system having a modular pneumatic shifting device. A teller conduit has a teller station and a customer conduit has a customer station. A housing having apertures connected to the teller conduit and the customer conduit has a teller gate and a customer gate intermittently obstructing the apertures. A differential pressure generating mechanism is connected to the housing. A plurality of sensors send signals to a programmable means when a carrier pass through the system actuating movement of the gates and operation of the differential pressure generating mechanism.