A two station, energy saving, telephone style intercom with a simple two wire connection, allowing 2-way conversation. It features a call button with adjustable call tone level. Both units are powered by 4x AA batteries (not supplied).Power supply[tab]6Vdc (4 x AA per unit)[br]Sensitivity[tab]<60mV（Frequency 1000 Hz)[br]Frequency response[tab]+3dB (300 Hz-3400 Hz)[br]Current consumption : in use[tab]<100mA[br]Current consumption : standby[tab]<5uA[br]Range[tab]200m[br]Dimensions[tab]210 x 92 x 68mm (each unit)[br]Weight[tab]360g (per unit)