Digital Hygrometer Thermometer 4-Pack, Hygrometer Indoor Humidity for Humidor, Greenhouse, Reptile Terrarium & Incubator - Indoor Room Temperature Monitor with Fahrenheit by DWEPTU

These 4 hygrometer/thermometer units are all within 0.1-0.2°F of one another and temp and humidity readings match my ZooMed Unit. All four of these cost less than the 1 ZooMed unit and now I can monitor both the hot and cool side of my terrariums. The units each come with 2 LR44 batteries installed, and the package came with 4 additional batteries (enough for replacement in 2 units). Downsides, the sticky pad has to be installed over the battery panel and I don’t see an option to switch to °C. I would buy again.

Work okay just watch the humidity. If to wet they die

These are surprisingly nice. I keep cigars in an assortment of "tuperdoors". I throw one if these in each bin. Small, don't take up much room, just put a battery in them and they work. Can't believe how inexpensive they are, they even came with mounting tape and extra batteries. Seem pretty accurate as well, they all show the same temperature, and the humidity level usually reads within a couple of percent of the Boveeda packs.

Good size

I ordered these mostly to check the temperature in our refrigerator and freezer. I think they have some issues with the moisture condensing in them. I get one reading then swap to compare with the other reading. Sometimes I have had poor readings. They are not really good for freezers. On the other hand they work well around the house. always nice to check the humidity in different places. At room temperature the accuracy seems to be good. One of them had the battery die very soon after I received them. this was not a problem as they sent 2 sets of extra batteries with them. they also included some Velcro tape for mounting them Over all I am happy with them but do not recommend for usen in freezers.