ContentSpecs.Dim.52mm x 46mm x 25mmWeight50gNetworkGSM/GPRSBand850/1800/1900Mhz or 900/1800/1900Mhz or 850/900/1800/1900GPS chipSIRF3 chipGSM/GPRS moduleSiemens MC55 or Siemens MC56 or Simcom300 or Simcom340GPS sensitivity-159dBmGPS accuracy5mTime To First FixCold status 45sWarm status 35s Hot status 1sCar charger12 24V input 5V outputWall charger110-220V input 5V outputBatteryChargeable changeable 3.7V 800mAh Li-ion batteryStandby48hoursStorage Temp.-40 C to +85 COperation Temp.-20 C to +55 CHumidity5%--95% non-condensingAuto Track Report a Geo-info at 30s intervals to the authorized numbers for 5 times:1. Set up: Send SMS t030s005n+password to the unit, it will report the Geo-info at 30s intervals for 5 times.(s: second, m: minute, h: hour). The setting must be in 3 digits and at maximum 255 in value.2. Send SMS t030s***n+password to the unit, it will reply SMS heaps of times3.Cancel: Send notn+password to delete the auto track Remark: the interval must not be less than 30s. Voice SurveillanceIn this mode, the user can dial up the unit to monitor the voice (please refer to 5.10 for instruction).Modes switch between track and monitor 1.The default mode is track . 2.Send SMS monitor+password to the unit, and it will reply monitor ok! and switch to monitor mode.3. Send SMS tracker+password to the unit, it will reply tracker ok! and restore to track mode.