Charging Voltage:DC 5V/500mA (Micro USB port) Internal Battery:Rechargeable and removable 830 mAh battery (3.7V) Operating temperature:-20to 50 Humidity:5% to 95% Non-condensing GSM module:GSM 900/1800/1900Mhz GPS Chipset:latest GPS (AG PS) GPS Sensitivity:-158Db GPS Frequency:L1, 1575.42 MHz C/A Code:1.023 MHz chip rate Channels:20 channel all-in-view tracking Position Accuracy：10 meters, 2D RMS Velocity Accuracy：0.1 m/s Time Accuracy：1 us synchronized to GPS time Default datum：WGS-84 Reacquisition:0.1 sec., average Hot start:1 sec., average Warm start:38 sec., average Cold start:42 sec., average Altitude Limit:18,000 meters (60,000 feet) max. Velocity Limit:515 meters/second (1000 knots) max. Acceleration Limit:Less than 4g Jerk Limit:20 m/sec Work time:60 hours in sleep mode and 10 hours in normal mode LED:3 LED indicators showing power, GPS, GSM status and other operation status. G-Sensor:2g