... GPRS data transmission 2Very clear satellite image view Auto Anti-theft and Vehicle Security SystemTracker MIC-GTK303I. Function and ... receiverMessage receiving, sending, with TK301(SMS), 303GPS/SMS positioning anti-theft products, realize monitor positioning function. Have 900/1800, 850 ... /1900 4types of communication frequencies. Auto Anti-theft and Vehicle Security SystemTracker MIC-GTK303