System Specifications: Carrier Frequency VHF110-120MHZ, FREQUENCY RESPONSE 50Hz-15kHz±3dB, Audio Output Freestanding 0-±400mV, Receiver Power Supply & Voltage AC220V/45-60Hz, Consume Power: 4WATER, Receiver Sensitivity 35dBu, Transmitter Transmit Power: 8mW, Modulate Mode FM, Power supply and voltage 9V (cascading battery)