... -2479MHz 2,Transfer rate:250K wireless voice door phone for long distance 500m 1V31,2.4G ISM ... Channel, full-duplex interoperability intercom, communication distance up to 500 meters aboveInstructions:1,Boot:Connect the ... flashes every four seconds3,CALLA:First press the ID number, then the CALL button, enter the main ... you will hear a "beep". Host can hang up on the call of the process. E:The ...