Dual radio system. System's unique split audio feature allows firefighters to clearly distinguish between simultaneous traffic on two radios (AM & FM) minimising the loss of critical radio transmissions. Intercom traffic and the fire dispatch radio (FM) are heard in the left ear, airport tower radio (AM) in the right. ARFF departments at 80% of America's major airports use the system 1310, making it the de facto standard. System provides full-duplex intercom among crew members and simultaneous radio transmit on two radios. Radio Select Module allows crewmembers to monitor and transmit over a third radio.