Scientology, a religion founded by the science fiction writer L. Ron Hubbard in 1952, is renowned for its veil of secrecy. The religion has its roots in Hubbard’s dianetics program, which he once described as a “mix of Western technology and Oriental philosophy.” Perhaps the most infamous technology to be produced by the Church of Scientology is the electropsychometer, or E-Meter, which is used for auditing, a question-and-answer session that is a core ritual of scientologists.

E-Meters are essentially ways of measuring electrodermal activity, or the ebb-and-flow of electrical activity on the surface of the skin. For scientologists, this measurement is interpreted as a way to “see a thought,” similar to a lie detector, although there is no scientific evidence to back up the Church’s claims. Over the years there have been several versions of the E-Meter produced by the Church of Scientology, which sells E-Meters to members for thousands of dollars apiece.

Read More: I Had My Personality Tested by Scientologists

Although the Church attempts to stop former Scientologists from selling E-Meters on eBay, there are dozens of listings for E-Meters selling for a few hundred dollars each. Recently, the Swiss maker behind the Play With Junk YouTube channel decided to pick up a used version of the E-Meter that the Church used until around 2006.

Inside an E-Meter. Image: Play With Junk/YouTube

After demoing how the device can be manipulated by squeezing its conductive handles, Play With Junk runs some electrical tests to get a better idea of how the device works. He then pries open the back to get a look at the mess of wires and circuit boards inside. He notes that the device seemed to be a “low-volume production” based on the amount of handwork that went into putting the hardware together.

It’s a lot of hardware for a device whose only use is measuring the electrical resistance of human skin. Although Play With Junk is impressed with the quality of the hardware components, he said the device is “certainly not worth thousands of dollars—maybe two hundred dollars or something like that.”