Yep, it's a narrow-range (~2 ohms) precision ohm meter, specifically a Wheatstone bridge[0]. Newer models have a microcontroller. There is a teardown video[1] of a newer model found on eBay. Scientologists spared no expense (e.g. $20 potentiometers, custom injection molded case)!
There's also an older teardown and a huge amount of info from Dave Touretzky on these things [3]
[0] https://en.wikipedia.org/wiki/Wheatstone_bridge
[1] https://hackaday.com/2018/07/19/whats-inside-a-scientology-e...