AN/PRC-77 Portable Transceiver

The AN/PRC-77 Portable Transceiver, also known as AN/PRC 77 Radio Set, is a man-pack, portable VHF FM combat-net radio transceiver manufactured by Associated Industries and used to provide short-range, two-way radiotelephone voice communication. In accordance with the Joint Electronics Type Designation System (JETDS), the "AN/PRC-77" designation represents the 77th design of an Army-Navy electronic device for portable two-way communications radio.

Source: Wikipedia — AN/PRC-77 Portable Transceiver (CC BY-SA 4.0)