The AT-640A/ARN Antenna is a receive-only VHF Marker Beacon antenna used on both fixed-wing and rotary-wing aircraft. The antenna meets the requirements of Military Specification MIL-A-5999 for electrical and environmental performance. The antenna is finished with a white Skydrol resistant polyurethane paint in accordance with Military Specification MIL-PRF-85285. The antenna has an operating temperature of -40°F to 160°F and experiences a drag force of 0.22 lb at airspeeds of 400 mph. Precipitation static is minimized through the use of a foam-filled fiberglass construction. The foam also reduces the effects of vibration, shock, and temperature extremes.