Review on Veanic 4-Pack Mini Digital Temperature Humidity Meters for Indoor Thermometer Hygrometer LCD Display Fahrenheit (℉) - Ideal for Humidors, Greenhouses, Gardens, Cellars, Fridges, Closets by Brandon Jaime

They work. All four hygrometers are accurate to within a few percent humidity and one degree Fahrenheit. I don't have a calibrated scale, but you can compare it with temperature or humidity. The battery life is quite acceptable. Each uses two LR44 size user-replaceable batteries in case they inevitably run out. I use them as a room thermometer/hygrometer at home and at work. Note that using an unsealed electronic device, including these meters, in an extremely humid environment for an extended period of time may damage it. You should probably take action if you see very high humidity (80% or more). . Unless you don't mind corrosion and death because you have three more. then the next one dies because it is not designed to withstand such an environment. then blame the manufacturer in a one-star rating from Revain. > You can disassemble your hygrometer if you have problems with the LCD. > Do this in a clean area. Dirt in a Zebra Flex Connector will make LCD problems worse, not better. Remove the batteries, then use the two latches on the bottom to pry up the meter. Be careful, the details will be scattered absolutely everywhere! Don't lose a single detail.>> The meter consists of five main parts: front panel, LCD screen (with Zebra Flex Connector installed), circuit board, base frame and back cover. Use an eraser or damp cloth (or t-shirt!) to clean the contact strip on the circuit board and make sure there is no dirt in the zebra cable that connects to the LCD. >> Don't tee off! That ruins the meter. :<Then reassemble the meter: place the LCD face down on the faceplate, with the zebra cord toward the slightly thicker part of the panel.>> If you see a curved part on the faceplate, you need to place it on the turn head Place a small plastic frame behind it, with the plastic tab close to where the zebra flex ends. Then insert the circuit board into the case and align the contact strip with the Zebra flex. Then align the battery. battery compartment cover and snap the back cover back onto the meter. Make sure all four clips snap into place. Finally, put the batteries back in and enjoy clear images again.