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

I bought these to use inside containers for PLA filament. They are accurate and surprisingly well-made, considering the price. I've bought three packs.

I do a lot of 3D printing and store my filaments in those plastic cereal boxes. I printed a rack that drops into the bottom to hold the spool of filament and it had a ring made for round hygrometers. I purchased these in a box of 10 (actually twice). They fit perfect. Not a laboratory device, but good enough. NOTE: Don't trust the numbers once you get below 10%. A bonus was they came with batteries installed. Don't know how long they have been in there, but it was better than having to use 10 of my own batteries. Great product for the price.

Great for filament

These are not the most accurate humidity and temperature monitors. They only read as low as 10% RH, even if the actual RH is 2%. What is Good: You can change the temperature between C/F. This comes in handy, although again, accuracy is not great. These will give you a general idea where your temperature and humidity levels are. That is about it, but then again, you get what you pay for.

I put these in all of my filament storage bins to check on how dry my 3-D filament is. What a great idea. I also put a few around the house just so I know what the humidity and temperature is. These are fantastic!

The work as advertised.

Been using these for about five months now. All of them seem to be accurate. Please note these only go down to 10%, which seems to be common for all of this style. If you need more accurate measurements below 10%, you will need to look somewhere else.

When this product arrived all of them seemed to be fine, except for one. The backing was popped up and the battery was corroded. No biggie, I’ll just use another one and replace the battery later. The next day, the new meter I was using made a loud snap sound from the back popping off, due to another corroding battery. So now I see, the batteries are cheaply made. I removed all their batteries and put them together to keep an eye on. 3 days later one of them literally exploded in my bag full of them (see picture). The meters themselves work great, the temps match up with my indoor temps. I can’t check if the humidity is 100% accurate but they all display almost the same humidity and temp when placed near each other. They are a simple meter with very little parts. If they come apart it’s quite easy to reassemble. It’s also important to know that the sensor is on the backing so you want to be careful not to block it when in use. I would have given this product a higher rating if the battery didn’t explode. If you buy this item just replace all of the batteries and it should be fine.

Very accurate, works very well, nice small size and easy to read. I use them for filament monitoring when in storage or in a reel box.

I don’t usually write reviews but I ordered 7 sets of 10 of these and one of the hygrometers didn’t work. I contacted the shop and they very promptly sent me a new box of 10. Amazing customer service and super product. Thank you so much!

I ordered two packs of 10 and of the 20, two of them are not working correctly. Other than that, the other 18 are within 2 degrees celsius and 3% humidity, of each other. Definitely not the most accurate pieces of equipment but for storing 3D filament, I’d say they are good enough.

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.

All items are here and are working as advertised. Bought January 1st, 2026 ... Expected delivery 12 January – 21 January The DATE of arrival was January 5th, 2026, and that was with the handicap of Canada Post being involved from BC to SASK. Great job, guys.