4-Pack Mini Digital Hygrometer Thermometer Gauge with Probe LCD Display Temperature Fahrenheit Humidity Meter for Incubator Reptile Plant Terrarium Sealed Containers Guitar Case

These devices have been working extremely well for me. The displayed temperature and RH for these two devices were almost always identical and when they deviated the deviations were either 1 degree for temperature and 1 to 2 % for RH, both well within the stated specifications. When I compared the displayed values with a more expensive humidity/temperature monitor the displayed values, again, were either identical or within 1 degree for temperature and 1 to 2 % for RH, indicating that these low cost devices are accurate well within the published specifications. For example, right now the two devices being reviewed both show 80 degrees F and 23% RH and the more expensive monitor is showing 80 degrees F and 24% RH, so the two devices being reviews are well within the published specification of +/-5% RH. For these devices, when RH increases the response time is very reasonable with a delay of less than about a minute. When RH decreases the response time is much slower than when RH increases and can take multiple minutes steadily decrease and to finally display the new, lower RH value. That type of response delay makes sense based on what I see when I remove the housing for the sensing element. It looks like the sensor is a resistance type humidity sensor and it will take time for the special salt between conductive elements to release moisture when the RH drops and to respond to the RH decreasing. What I believe to be the sensor's data sheet shows that the sensor is a +/-5% RH device and these two temperature/humidity devices are displaying RH that is will within +/-5% RH. Reading reviews it appears that some confusion exists regarding what is considered to be errors in displayed RH. The specification that I see is +/-5% RH. At the limits that specification means one device could be 5% low and the other one 5% high and still be within specifications. For example, if the real RH is 35% then one device showing 30% and another device showing 40% is within specification. I observe that the devices I have have been using are working at what appears to be about +/- 1% RH, which is excellent. For reference, when I checked on other more expensive sensing elements I saw +/- 2 % for the specification.

I use this for my leopard gecko's tank, its nice that it comes in a 2 pack to be able to read both sides since they need a warm side and cool side. It allows me to quickly check the range of temperatures abd helps me to be able to adjust the humidity when she is shedding.

5 stars for price. but off a couple of degrees - good enough for my brood boxes to make sure I am in the range

The display portion of this instrument reaches out to the sensors via a cable (about 4 feet long), making it possible to measure, for instance, the temps in a 'fridge. It is surprisingly tiny, but the display is still easy to read. The display can be mounted by using the included suction cup or the two sticky pads. The unit responds reasonably quickly. It took less than 5 minutes for it to match my much larger unit to within 1% of hunmidity (46%/47%), and 2 degrees of temperature (76/78). I have no way of telling which unit is "off". Maybe they are both off! Naturally, being from china, neither this or my big unit came with accuracy specifications. Or any specifations, for that matter. If you need to measure humidity and temp, it's hard to ignore this unit. Inexpensive, small and easily hidden, it works good enough for most non-laboratory applications. And because you get two for the price of one for roughly the price of a cup of coffee these days, it is affordable...if you but skip one morning's cup, that is!

The product seemed to work fine till it was tested against other thermometers and humidity sensors. I let the sensor sit for 20 minutes to make sure it came down to room temperature and tested against other thermometer and came to be 8 degrees off from the other instruments. The humidity sensor had the same result, I let it set and and stabilize and was off by around 15%. It’s not a terrible product for the price point but would not recommend for any decently precise use case. The probe being separate from the readout is a nice touch. I wouldn’t recommend for incubators but would be alright for something like a greenhouse.

Use these to monitor temp and humidity in incubators for baby squirrels. the temp seems to be right on and it lets us monitor the boxes to not let them get too cold. No problems with them so far and we are happy with them

I don't feel like these are super accurate. I got them to use in my dart frog terrarium and so far I'm not super impressed. they take a long time to adjust when there is a temp change. It seems that the humidity is just not accurate at all as it rarely changes even after I've just misted. I would not recommend these

I purchased these for my egg incubators to keep an eye on hot and cold spots. But before I could use them for the purpose I bought them for, I added 2 reptiles to our home. I stuck 2 in each enclosure to monitor temperature and humidity and they work great! I had to order another pack for my incubators.