General Features:The M4AC40 is fully charged from the factory. This unit is designed to operate at outdoor ambient temperatures as high as 115 -¦F. Cooling capacities are matched with air handlers and furnace coils that are AHRI certified. The unit is certified to ETL. Exterior is designed for outdoor application.CasingUnit casing is constructed of heavy gauge, Galvanized steel and painted with a weather resistant powder paint on all grilles, panels, pre-paint on all other panels. And had 500-hours salt spray tested.Refrigerant ControlsRefrigeration system controls include condenser fan, compressor contactor.Scroll CompressorFeatures include low vibration and noise.Condenser CoilThe outdoor coil provides low airflow resistance and efficient heat transfer. The coil is protected on all four sides by grille panels.