ThlevelDigital Thermometer Hygrometer Temperature Humidity Meter Gauge for Greenhouse Cars Home Office 4PCS

...scientific devices - they are small modules that look as if they were made to 'clip' into and become a part of another larger entity.Two of the four are white and two are black and sit quite comfortably on a flat surface. They screen is not illuminated and therefore it needs to be in a lit area to be easy to read the humidity % and the temperature [which is shown in Celsius].The device is set to measure once every 10 seconds and the seller clearly states the latitude of accuracy for both functions. My own tests show that putting all four together in one place will give readings within 1% to 3% for humidity and potentially 1 degree of temperature [which is acceptable given that there is no provision for any reading between whole numbers - so one unit may say 20 degrees when it's actually 20.4 degrees and the next unit might show 21 degrees when it's actually 20.8 degrees].The units run on 2 small and readily available button batteries and whilst there is no on/off switch they can be stopped by removing the batteries and replacing them when you want to use the device.I am quite taken with them and have ordered another set of 4 so clearly I recommend them for their simple but effective use.

I used these items to check on the amount of moisture that existed inside of my wardrobes as sadly, we live in a very damp house. They worked perfectly and gave virtually identical temperature readings in all four wardrobes and it was only the humidity readings that varied slightly. So, I will firstly be tackling the problems by deploying use and dispose type Dehumidifiers for this Autumn and Winter before tackling the more complex identification of the source of the dampness and treating it. I suspect that will be the expensive part!! Stay warm dry and above all, safe. Terry.

If you bare in mind that temperature has a 1% accuracy and humidity a 5% accuracy as per the specs, then these perform well; all well within those ranges of each other. When moving the device I'd advise giving it 30 minutes to an hour to "settle" as they seem slow to adjust, maybe taking an "average over time" which is probably sensible. I compared these to another unit I have and they read very similar (well within 1% and 5%) so I trust them. If you get one not displaying correctly, try re-seating or replacing the batteries.

These three displays are great for placing discreetly in rooms to understand in a quick way the temperature and humidity. However, they are very small at measuring about 2cm X 5cm. It's also clear that they ar designed to be inserted into something as they have release mechanisms on the side meaning they aren't the most visually appealing, but they are small enough to go unnoticed to all but the most discerning observer.

I use these in vivariums as they are small, unobtrusive and show temperature and humidity. They are cheap enough that you can have a few of them placed around the vivarium to show whether you are providing a good temperature range. They last a couple of years before needing new batteries, 2nd the display can become patchy after 3 or 4 years. But, I think they are the best available for the money for vivariums. They are usually accurate to within 1 degree Celsius.

I actually only needed one to measure the temperature in my garage but decided on a pack of 4 as the reviews were good and they were so cheap. Right out of the pack they measured pretty much the same . I moved them to 2 other locations and the results were similar. I have put one in the fridge (amazed to find out how warm my fridge is!!), and put the others around the house. I have just bought another pack to put in other places - cant go wrong for the price. A great buy!

They all display different levels. I reset them all in an attempt to recalibrate them, but they all seem to behave differently even when placed in the same position. I have no idea which reading to believe, so all I can say is that they're cheap and pointless.

Bought these to check temp in different areas of the house. Work fine but are not super accurate. Checked against a known source and they were all about 1 degree high. However they have done they job required.