Small size and lightweight, easy for carry. 2. Black shell, easy to hide, perfect for tracking vehicles, teens, spouses, elderly persons or assets. With two powerful magnets inside, easy to attach to vehicle sure, no extra installation need. 3. All you need is a working SIM card NOT included! to insert into the device, then you can track and map with Google Maps in real-time over the Internet. 4. Dial SIM card number, then you can hear voice around this tracker, with no light and no noise. Note:. 1. This GPS tracker cannot work if a SIM card is not inserted. It can work with or without the mobile APP, so you can have real-time tracking either using SMS or the mobile APP available for Android and iOS.. 2. Only GSM SIM card works in this model. GPS locator. 3. Please make sure GSM SIM card supports making calls, sending messages, GPRS network.. 4. There will be an extra cost of data usage when you use with the SIM Card.