6 Pack Mini Digital Thermometer Hygrometer,Indoor Temperature and Humidity Gauge Meter Monitor Fahrenheit (℉) for Home,Greenhouse,Jars

I verified they were correct with lab approved method. You can too!Bought 6 pack, all were correct within + -2% RH ! Impressive. Make a salt shush ~ 1/8" deep in bottom of cleaned and dried tomato sauce jar. Hot glue a paper clip/ wire hook to the inside of the lid so you can hang the device on it's end. Kosher salt (pure sodium chloride, not iodized) slush with water in bottom will at room temps ( 68-95deg F) makes a 75% relative humidity atmosphere in the jar. Potassium Carbonate slush makes a 43% relative humidity (at 50-77degF). Hang device an inch or more above the slush. DO NOT get slush on the device! Make sure no pure water drops on the inside of jar. Allow a half hour for reading to settle in. For the small price they are FANTASTIC! (please, no questions)

So tiny! I put them all around the house where I have plants.I put them all together when I first opened the package and left them for a few hours until they all showed almost the same temp and humidity levels, to make sure they were at least consistent with each other, and they came to within one degree and one percent of each other. Great value for the price if you ask me. They’re so discreet too!

worked for what I needed, problem I have is batteries dont last very long and its honestly cheaper to buy another set of sensors than to buy batteries for the sensors. Which is kinda crazy and contributes to waste

These are not 100% exact and precisely accurate with one another. But they are very close to each other and other outside hydrometers and thermometers. They were accurate enough to suit my needs. They only vary within a degree or two and that's not bad for the price.

Bought these when we moved into our house to see where the moisture was coming from. Have them in every room and I even bought a second pack for upstairs. So easy to use.

I bought a set of 6. When I received them, and opened the box, only four were working and they all had moderately different humidity levels displayed, although the temperatures were pretty close to each other. After I set the four that were working out on a table together for an hour, they did all get much closer to each other in terms of similarity of humidity readings. I don't know how accurate those readings were, because I don't have any other hygrometers to compare them to.Then I tried to get the remaining 2 to work. One has never worked, despite trying new batteries. The other worked for a day or two when I put new batteries in it. And then died. I am not going to waste any more batteries in that one. So...4 out of 6 at least display similar numbers to each other, and are still running after several months. They are in some pretty damp environments, although I am careful to avoid getting water directly on them. (terrariums with pitcher plants)EDITED: The company contacted me and offered to send me some additional hygrometers. The new ones arrived very quickly, and I have to say...these are all working perfectly. I still don't have any way to check their accuracy independently, since they are the only hygrometers that I have...but they are all within a point of each other (and the working ones from the original batch) when placed in a group on a table. And all seem to have functional batteries. I am thinking that my original purchase and review might have been based on hygrometers that had a rough time in the mail, or had a bad batch of batteries. These new ones are fine!

Great still working years later on the same battery actually need to buy a few more these work well. Great at keeping the temperature measured properly according to my temperature gauges, battery life like instates is awesome , size is good few inches, looks nice, does not have bluetooth good old school analog, very clear so it is easy to read.

Humidity all the same, temperature was different on all the units. Never varied by more than 5 degrees f