The public has had a tense relationship with the TSA’s full body scanners for as long as they’ve been around. As it turns out, we were right to be worried. According a recent report that was first covered by Wired, there are several ways to get a weapon past these scanners, and most of them are shockingly simple.

For example, in 2010, a man named Jonathan Corbett posted a YouTube video in which he claimed that, because of the black background on the scanned images, a gun would not be visible if a person hid it on their side or sewed into a pant leg. The TSA denied the claims at the time, but they appear to be completely valid. A team of researchers from three different colleges tested Corbett’s claim and it worked.

Even worse, hiding a gun at your side is just one tactic a person can use to smuggle contraband past a scanner. Those same researchers also found that a thick layer of teflon tape is all that’s required to render a gun or knife secured to a person’s back completely invisible on a scanner image.

But wait, there’s more! What fun is a scary terrorism story if it doesn’t involve explosives of some kind? Turns out those are fairly easy to conceal as well. Specifically, a layer of plastic explosive can be wrapped around the torso, making it look just like flesh to the invasive eyes of a TSA scanner.

It’s not all bad news, though. The scanner that failed these tests, the Rapiscan Secure 1000, has been phased out at most airports. Of course, they do remain in place at the various government security checkpoints around the country, like courthouses and jails. Good thing no one ever tries to take weapons to those places!

If you’d like to run some wacky security checkpoint tests of your own, you’ll be glad to know the researchers who conducted these experiments were able to purchase a full body scanner on eBay. Comforting!