Unlike bulky portable or wall units, only a small hole is needed to link the outdoor compressor/condenser to the stream-lined air-handler mounted inside. The noisiest and largest parts (the compressor and condenser fan) are isolated outside resulting in saved space as well as less indoor sound pollution. Split A/C’s deliver more Cooling Efficiency per BTU than any other add-on-unit and match the effectiveness of central air conditioning systems without the expense of retrofitting ductwork.