I originally got the Accurite combination but when I switched to Herpstat I noticed they have a hygrometer probe. I sent Dion at Spyder Robotics a message and he told me to save my money and get the Xikar model from the link below (the rectangular one at the bottom) and stated that's the model they use to ensure their probes are calibrated correctly.

https://www.xikar.com/products/humid...l-hygrometers/

I called Xikar and spoke with Kevin about the 10-15% difference from my Accurite to the Xikar to see if I had to calibrate the new one. He said it did not need to be calibrated and was good to go out of the box. I mentioned having 3 enclosures and I wished they had a wireless set-up and guess what....they do LOL

So I made a quick visit to amazon and ordered this with 3 sensors....

https://www.xikar.com/products/humid...-hygro-system/

So I've been comparing all 5 hygrometers and the Xikar units are all within 1-2% of each other while the Accu"wrong" has been 10-15% off...

Hope this helps...stay away from cheap dials and spend a couple bucks on something that will give you good numbers (at least from my experience).