Through Mitsubishi Electric’s advanced controls technology, the indoor unit is powered by the outdoor unit. Three polarity sensitive wires plus a ground conductor run from the outdoor to the indoor unit, providing both power and data communication. An advanced wireless remote control is standard on all ductless models. An optional wired on-the-wall controller is available for wall-mounted/floor-standing indoor units on INVERTER systems (also requires MAC-397 lf adapter). While standard on SEZ-KD ducted units