I use two in each cage. i use a digital unit that I place where it doesnt get direct spray and not in basking light. i use the other one on the other side of cage and a little lower than the digital. they both read temp and humidity. the digital one has two probes and the other just uses velcro
I got a small (baby) cage so it's getting sprayed heavily. Short of taking it out each time there is no way to avoid it getting wet. I guess that's what I'll have to do.