Full Duplex Wireless Handheld Two Way Radios

1.Battery: Rechargeable li-ion 2.Operating power: DC 3.7V 3.Current: 150mA 4.Working temp: -40~+70℃ 5.Transimit power: 20dBm 6.Received sensibility: -100dBm Full Duplex Wireless Handheld Two Way Radios AFH for Soccer Referee TA-521-RF Full Duplex function: Talk and listen at the same time , Without PTT button , Workable distance about 300M(master phone and extension phone) AFH technology: Adaptive Frequency Hopping when the channel disturb Team working: - 4 pack in a group -