The Honeywell KXP-755 ATC Transponder is an important unit of the Air Traffic Control Radar Beacon System. The function of the KXP-755 in the aircraft is to send a coded response to a coded interrogation transmitted by the air traffic control station. The Secondary Surveillance Radar interrogates the KXP-755 in three different modes, Mode A, Mode B and Mode C, which is capable of replying to interrogations with a coded pulse group on a carrier of 1090 ±3 MHz. Three memory gates are included in the KXP-755 to record the coincidence of a Secondary Surveillance Radar decode. The weight for the KXP-755 is 4.9 pounds, and the height is 5.0 inches, width 2.25 inches, length 10.00 inches. The temperature range on the KXP-755 is -54°C to +55°C.