The Mercury 2WDP064 is a reliable and easy-to-use intercom system, perfect for private conversations with delightful 1-melody signal sound. Featuring simple wiring with 2 lines of non-polarity and full direct communication between two stations, it offers a range of up to 300 meters with 0.6mm wire. Easily mounted on a wall or desk, it's powered by either DC 6V (4x LR6-AA 1.5V batteries) or AC Adaptor DC 6V.