This product adopts double modes to work which is with GPS global positioning system and GSM mobile phones machine station positioning system. You can simply search the position of the target through the computer or the mobile phone which installs GSM card. The products also can transfer automatically into GSM positioning system in the condition of out of GPS positioning system...with double position system, the products also support the work of four frequency channels which is universal used. They are 850MHz, 900 MHz, 1800 MHz and 1900 MHz. The products are widely used in cars and ships tracking position with integration and mini design and convenient install. As long as the automobile start, GPS fixes position immediately automatically. The products' safety orientation is in our hands with their low power consumption and high efficiency, without needing networking platform and monthly rent.