Gsm quad-band, gps+gsm+gprs wireless network High sensitive gps chipset Real-time tracking Built-in gsm&gps antenna Built-in on/off power switch, Wide voltage input range Built-in acceleration sensor for vibration alarm Support acc detection, Real-time reporting car status Built-in 450mah battery for alarm when the power supply is disconnected unexpectedly tele-cut off (petrol/electricity) function mainboard support voice monitor function Check location information via sms and gprs(tcp) built-in cpu, Restart automatically Three led indicators: gps-green; gsm-blue; power-red Check location via platform Specifications: Gsm: 850/ 900/ 1800/ 1900 mhz Gprs: class12, tcp/ ip build in gsm module Gps: sirf3 Gsm antenna: built-in quad band Gps antenna: built-in gps high gain ceramics patch antenna. Gps channels: 20 Tracking sensitivity: -159dbm Acquisition sensitivity: -144dbm Locating time cost: hot start: