annunciator system is designed with a superior dual counter dual active infrared beam technology. It emits a continuous invisible beam across the doorway to the reflector. When either beam is interrupted, it announces the entrance and exit of customers with a pleasant distinguishable chime sound. The dual Entry/Exit counter registers a count any time the beams are interrupted. Each event is counted, recorded and registered by the built-in digital counter and can be viewed and compared later in both modes. Other features include a new electronic chime with adjustable volume control. Ideal for strip malls, office buildings, liquor stores, large retail establishments, warehouses, parking structures, donut shops, medical offices, drive-thru fast food restaurants or just to monitor In and Out traffic.