The Friedrich KEVS16B33B unit uses R32 refrigerant with low Global Warming Potential (GWP)! R32 refrigerant is more efficient than R410A, resulting in a lower GWP. Kuhl's smart room air conditioners also feature Quietmaster Technology, making them 45% quieter than competitors' products. Quietmaster technology features sound-blocking insulation, a rotary compressor mounted on rubber grommets and steel inner walls. Not only is it better for the environment with its R32 refrigerant, it will also save you money on your electric bill and run efficiently for years to come. The Friedrich Kuhl Series KEVS16B33B Air Conditioner comes with a neutral gray front face plate, to blend into virtually any room. With its Precision Inverter Technology, the compressor runs at different speeds. It will run at a higher speed to cool your space quickly then, once it reaches the set temperature, the compressor slows down. This allows the room to maintain a set point without constant shutting down and re-starting. Featuring 16,200 BTUs of cooling power on high and a low of 7,750 BTUs, the Friedrich KEVS16B33B also includes an electric heater with 10,700 BTUs of heat. Because of its variable speed compressor, the new Kuhl units are more energy efficient, lowering your energy use as well as wear and tear on the compressor. It will cool a large sized room that is about 550 - 700 sq. ft. The KEVS16B33B can be installed either in a window or mounted in your wall. It does include heavy duty side curtains for window installation.