Surface to diver unit (transceiver unit), allows communication with any number of divers wearing wireless comm units. Direct communication with PTT walkie-talkie, it uses 6V DC lead battery and allows up to 48 hours of operation. Can be powered with a 12V DC source. Activated only when the antenna is connected to the unit to prevent unwanted loss of power. It comes with 10mt (approx. 33ft.) transducer cable length. Available in different lengths on request. Long cables may require amplifier mounting. Also includes: Headphone connection Volume control Speaker Water resistant case pressure compensation valve Battery charger Easy to read LED battery tester which shows the power status of the battery Transducer cable Bag Microphone Available accessories for the unit: Audio out cable. (code 8590) Headset. (code 8589) Tuner for >50 meters M105 Antenna. (code OR008609) Splitter for connecting 2 antennas with M105 (code OR023001) External power cable (code 8594)