... tracker/bicycle gps tracker/gps sms gprs tracker vehicle tracking system GSMFrequeny channel850MHz/900 MHz /1800MHz /1900MHzGPRSClass 12, ... etc working conditions andOther circumstancesFunction:1, OverSpeed alarm2,Vehicle alarm to mobile phone3,Control by mobile phone ... -corrosion and anti-interference3,Support wide voltage, all vehicle are available, convenient and shortcut4,Unique appearance,Striae ...