Overview: GPS-830E/G GPS wrist tracker is a stylish device with built-in GPS and GSM modules and high performance antenna System operation is both by SMS and monitoring center (GPRS) LCD screen displays system setting/coordination data/satellite indicator Its watch design will satisfy your loved kids and elders Features: GPS SiRF-Star III chipset fast fixing the position even at a weak signal status Works worldwide, supports 3-frequency GSM 900/1800/1900MHz Receive phone calls, SMS, and GPRS in three way communications Monitors can track the device without interfering him, live real-time tracking SOS button send out exact location for immediate rescue/action Independent SOS button which will send GPS information via SMS for 1 to 5 preset numbers System setting by SMS free Low battery notification before the battery runs out, worrying free on why the locater wouldn’t respond for this kind of situation Speed limit alarm Multi-user management on website (GPRS mode) It has data logging function and records up to 20,400 way points The wrist GPS tracker can display the time and positions of the wearer With A-GPS, the receiver can acquire satellites, and provide accurate position data instantly on demand, even under poor signal conditions Specification: GSM/GPRS: GSM/GPRS (module): Simcom300 tri-band GSM module (GSM900/1800/1900MHz) GSM antenna: built-in Protocol: supports TCP transmission GPS: GPS module: SiRF III 20 channels Protocol: NMEA-0183 compliant protocol GPS antenna: built-in active high sensitivity antenna Accuracy: 1 to 5m Update rate: 1Hz Start time: Cold start: 42s Warm start: 35s Hot start: 1s Electrical: Operating voltage: 3.4 to 4.5V Charge voltage: 4.5 to 5V Standby: 15mA