In 2005 Kathy Thomas, an animal rights activist, had been aware for years that she was being tracked and followed by the FBI. But one day she noticed the tracking had stopped.  The FBI agents were no longer following her on a weekly basis.  She figured the FBI had given up on her, but after a few weeks she confronted one of the agents she knew had been tracking her.  After the confrontation, she was suspicious that law enforcement was still monitoring her, so she decided to check for a GPS vehicle tracking system under the bumper of her car. She was not surprised to find a small black GPS tracking system under the rear bumper of her vehicle.

Last week Wired Magazine obtained the GPS tracking device found by  Kathy Thomas on her car in 2005. As part of its coverage of Thomas’ plight, the tracking system was sent to iFixit for analysis. iFixit is well-known for its tear-downs of electronic devices.

Overall, the tracking system is fairly simple and contains four major parts: a magnetic mount, a GPS antenna, a transmitter/receiver unit, and a battery pack. Its simplicity likely has a lot to do with the fact that the FBI doesn’t want you to ever find it unless you’re looking for it, and something more complex would be easier to find.

The GPS tracking device is powered by four lithium-thionyl chloride D-cell batteries, presumably so agents can track you over time. With a rating of 13,000 mAh on each cell, the GPS device would likely be able to stay powered for 10 to 20 years. Another important consideration is making sure it stays on the car: iFixit said that the magnets are so powerful that the devices mounting brackets need to be broken off it to remove it.

To see photos of the device, go to IFixit’s website here. Here are some  interesting highlights from the teardown:

• The GPS tracking device’s antenna is actually made up of two: one for the GPS positioning, and another used to send that data to FBI transponders.
• iFixit said that it was apparent that the FBI didn’t want anybody tampering with the unit: screws were coated with threadlocker, requiring a power drill to pry the device open.
• The GPS tracking device appears manufactured by the FBI itself, and some of the parts are fairly old: the GPS signal processing unit was from 1999.