RADIO SET AN\PRC-77 IS A SHORT RANGE,MANPACK,FREQUENCY MODULATED(FM) RECEIVER-TRANSMITTER USED TO PROVIDE TWO WAY COMMUNICATIONS.THESE RADIOS ARE ALSO PART OF RADIO SET AN/ GRC-125,AN/GRC-160 AND AN/VRC-53. THE RT-841/PRC-77 IS TUNABLE IN 50 KILOHERTZ(KHz) INCREMENTS OVER A FREQUENCY RANGE OF 30.00 TO 75.95 MEGACYCLES (MHz) TO PROVIDE 920 CHANNELS.THE FREQUENCY RANGE IS COVERED IN TWO BANDS, THE LOW BAND IS 30.00 TO 52.95 MHz: THE HIGH BAND IS 53.00 TO 75.95 MHz. Olive Drab in color. Weight of the RADIO, PRC-77 is 10.5 LBS, without battery. THE AN-PRC-77 WITH THE SHORT WHIP ANTENNA HAS A RANGE OF 11 MILES.THE AN-PRC-77 with THE LONG WHIP ANTENNA HAS A RANGE OF 22 MILES. RANGE IS BASED ON IDEAL OPERATING CONDITIONS. UNITS ARE TOTALLY REBUILT AND GUARANTEED FOR A PERIOD OF 6 MONTHS, PARTS AND LABOR.