-Interfaces the David Clark H3530 / H3531 ground support headset to the aircraft. -Contains a momentary Push-to-Talk (PTT) Switch to key the headset's microphone. -This is critical for preventing background noise from interfering with pilot communications between the tower and crew prior to and during pushback. -Belt clip allows for easy attachment to belt or clothing. -Quality components and construction provide added durability for dependable performance in extreme conditions. -Cords are shielded against RF interference and are chemical-resistant for superior durability.