Functions:2 speed dial alarm buttons and one SOS button;SOS signal can be sent to the control center if the SOS button is pressed, so as to indicate the users location precisely;The guardian can search the users location directly through message without the need for monitoring system;Display time, speed, coordinates and altitude;Support active and passive monitoring;Support time setting and continuous/discontinuous tracking functions (System support is required);Support the electronic fence function, and give alarm if exceeding the designated range (System support is required);The monitoring center can search the users location through message/GPRS (System support is required);Track recording function, historical track playback function (System support is required);Support GTE protocol, and provide GPS operation management system of B/S or C/S framework Specifications:ItemSpecificationWorking frequencyGSM/GPRS double-frequency 900/1800MHz; 850/1900MHz GPS1575MHzAppearancePortable monitorExternal dimensions80 (L) × 55 (W) × 24 (H) mmShellPC+ABSButtonPower on/off button, SOS button, 2 phone buttonsUSB interfaceMini USB (12PIN), charging/earphone interfaceSIM card holderBuilt-in SIM card holderBuilt-in MICTalking and monitoringDisplay screenMonochrome screen, 64*48 pixelsPower supply3.7V rechargeable 800 mAh Li-ion battery, 5V charging inputEarphone12PIN USB interface with MIC (optional)Standby timeUp to 72 hours (subject to the network signal environment and use mode)Current consumptionDuring communication: Below 250 mA on average During standby: 2-3 mA (power saving mode)Surrounding environmentWorking temperature: -30∼+70 Storage temperature: -40∼+80 Working humidity: 20∼90 (avoid condensation)