Sourcingbay Remote Control GPS103B+ Car Vehicle Realtime Tracker for GSM Gprs GPS System Central Door Locking System, Dual SIM GPS car tracker with fleet management, central door locking and Dual SIM. Keep track of your car in real time with this versatile GPS tracke 2 different SIM cards(2G network) can be inserted. This GPS Car Tracker is the ultimate safety device for your car, van, truck, or even the entire vehicle fleet You'll be able to remotely lock the door of your car and lock anyone who is inside of the vehicle until you get to the car If using a GPRS enabled SIM card, you'll even be able to monitor real-time movement of your vehicle with the supplied software on your computer. On top of that, you'll also be able to record the audio inside the car using the detachable microscope This GPS trackers need to use a local sim card for 2G network, 850/900/1800/1900MHZ(sim card not included). Kindly notice: recently some sim card carrier have dropped 2G service, please confirm if your area can use 2g network sim card long time. Otherwise, please check the item description carefully before purchasing. thanks.