“I'm not quite sure what chemistry is in these slides, but the price is pretty eye-watering, but as they say, it is for peace of mind on your precious fish, so it's "because they're worth it". I hadn't put any new slides in my monitor for the last six months because of the cost, so then it just monitors temperature and endless erroneous out of water alerts, but thought I would treat my fish to a bit of extra security for the start of 2019.
Way over-packaged, you could easily fit a dozen or more of the slides in their existing inner pack into the cardboard box they come in, if they put the slide in a pack more appropriate to the actual size, you could probably fit over 100 in.”