... .20UV rated voltage: AC 220V 4.8V-6.0V Communication distance:3-10 Km working band:230-450MHz Functions and features ... , auxiliary lighting luminous display, three colors to choose.10, the call volume can be adjusted. Ring volume can be adjusted.11 ... , cell phone headset with car charger and microphone socket.16, long distance calls, in the broad perspective, no interference can talk freely ...