Each U-Match heat pump is powered by Gree's energy efficient G10 inverter and a variable speed compressor. Our G10 inverter technology saves energy, reduces outdoor noise and keeps room temperature steady by eliminating the harsh starts and stops of conventional systems. And they're available in a full range of capacities to perfectly match any size space, large or small. Best of all, the ultimate in reliable room comfort is generated with Eco friendly R410A refrigerant. G-10 Inverter control Heavy Gauge Steel Cabinet Sound Levels down to 56 DB Low Ambient Cooling down to 5 degree F R410A Refrigerant Multi-point Diagnostics