Features: Real-time locating and tracking: it can transmit the longitude and latitude coordinates by SMS or GPRS. By this, you can find its location Geo-fence function: it will send an alert to the authorized cell phone numbers when it breaches the restricted area that you set up before SOS function: press the SOS button and the GPS tracker will send a help alert and exact location to the authorized cell phone numbers for immediate rescue Excess speed alarm: the tracker will send the excess speed alert to the authorized cell phone numbers when it is excess speed Low-battery alarm: it will send an alert to the authorized cell phone numbers when the tracker is low battery Two-way talking communication: You can talk with the tracking target via the GPS tracker just like a cell phone and also can listen to the sound around the GPS tracker in 3 meter secretly