GPS SiRF-Star III chipset fast fixing the position even at a weak signal status Works worldwide Support 4-frequency GSM 850/900/1800/1900 MHz Report GSM operator and cell ID to fix the position when indoor or other NO GPS signal place Work in phone call, SMS and GPRS three way communications Navigate you to find your friends and kids whose phone number is saved in your WT-8 in advance SOS button send out exact location for immediate rescue/action Via SMS or GPRS Show alarm icon and beep on host computer's tracking map at real-time Geo-fence alarm, send out via SMS or GPRS to the tracking map at real-time Over-speed alarm and compass and data logging function System setting by SMS or USB or soft keyboard, to connect and use PC software interface Multi-user management on website (GPRS mode or SMS modem mode)