"MODEL NO. OF AIR CONDITIONER IS MA-3D; INTENDED FOR GENERAL PURPOSE AIRCONDITIONING OF AIRCRAFT AVIONICS COMPARTMENTS DURING MAINTENANCE AND PREFLIGHT PERIODS; COOLS MAINTENANCE SHELTERS, PORTABLE HANGER, ETC.; USES REFRIGERANT R-134A; PROVIDES VENT AIR OR COOL, DEHUMIDIFIED AIR AT A TEMPERATURE OF50 DEGREES F; OPERATES ON THE CONVENTIONAL VAPOR-COMPRESSION CYCLE"