10-Pack Mini Thermometer Hygrometer, Small Digital Electronic Temperature Humidity Meters Gauge Indoor LCD Display for Greenhouse, Garden, Cellar, Fridge, Mason Jar

These little sensors are so cheap and affordable that I am worried they'll break. But lo and behold, still going strong. I was also concerned they wouldn't be accurate or precise but in all of my testing, they've passed with flying colors.

Perfect for most applications Accurate & easy to read. Great value

Good enough. Lighter than other ones I’ve purchased slightly, however reporting is consistent, that’s all that matters. 10/10

They function great, but are incredibly fragile. Be careful if inserting them into a housing, they may come apart.

These work great if you need to monitor the temperature of any items. We put them in the bags with our "herbs", and they kept the temperature right where it should be!

Everything was great except the batteries were already running. That being said were they just activated or have they been running on a shelf somewhere for 6-8 months? Other than that nice size and currently working.

It made a really big difference to know the humidity inside the jars was correct or not in order to take action if needed. Super easy to use kind of idiot proof to be honest.

These are nice hygrometers that have many uses. The quality is decent for the price point, and they all seem to be reasonably accurate and track together. I haven't tried calibrating them to a national standard for accuracy, but they aren't labeled as NIST certified, so that's not really an expectation. The humidity values track within 1% of what I'm getting from electronic equipment with internal sensors, so I'd say they're accurate enough for anyone looking at one of these for hobby or home use. The price for them seems fair as well, as they work out to be about $2 per piece.

A great deal for 10 units. Temperature & humidity great for jar storage DIY projects and greenhouses, Reliable and efficient. I recommend these to any serious gardener.

Nice hygrometers, show temperature in F or C, humidity is measured pretty well and precise between 20 and 99%. Lower than 20% shows only 14% and 10% values. Highest temperature I measured was 55C. But maybe it can show higher, I didn't test

Hard to read unless directly in front of you. I mounted this in the lid of a dehydrator for drying filament and it does nothing for me in that orientation. In applications where you can look at it directly, no problem. Just be aware.

Perfect for the job at hand.

Works well. No issues.