If your favorite piece of headgear is made of tinfoil, this Counter-Surveillance Device should be right up your alley. It can detect and block all sorts of privacy-invading technologies, such as wireless video, laser audio, phone taps, and GPS tracking. Just keep it in your pocket at all times to make sure the FBI doesn't get to see you buying Doritos and renting Evil Dead for the 50th time, since you know that's what they spend their budget on.
Unfortunately for the true paranoids out there, this won't stop cameras from taking pictures of you, even though the technology to do that exists. Furthermore, it won't block long-range brain scans that extra terrestrials may or may not use to download your memories for research on the impending invasion. I mean, without that you're basically throwing your $350 away, am I right?
source- scifi.com