Work parameter 1, Model: VD500 2.Exterior Size: 69.5(L)*45(W)*12.4(H)MM 3, Interface: USB2.0 4, Wireless Frequency: 800MHZ Transmit RF: 824 to 849MHZ Receive RF 869 to 894MHZ 5, Receiving Sensitivity: -106dbm 6, Storage Temperature: -30 to +70 7, Operating Temperature: -20 to +60 8, Relative Humidity: 5-85%RH 9, Work Voltage: 3.0V-3.6V 10, Work Current: Send520MA (MAX) Receive150MAMAX) Dormancy18MA (MAX) 11, Support Protocol: CDMA2000 1X*RTT, IS707-A, FCC IS-95A compatible 12, Operating System: Windows 2000/XP/VISTA