Dimensions: 1.7 x 1.8 x 0.7", precisely locate indoors and outdoors, able to prevent theft of vehicle, cargo and strong box, and monitor and protect the old, children and pets, and covertly track. It is a server-based service, more advanced technology than GPS. It positions and tracks various remote targets or objects in combination of the signals of CDMA (800/1,900MHz) base station and GPS satellite. User can get the position information via message or Internet.