IN SHORT: A tremendous improvement over my 5-year old LaCrosse indoor/outdoor temperature/humidity solar-powered station that finally, mercifully, died. DESCRIPTION > Both the sender and the receiver are powered by 2 ordinary AA batteries each, which are easy to replace. > No complicated setup. No on/off switch. No clock to set. No mode buttons. No synchronization procedure. Just insert the batteries in both units and they start working. > Easy to read at a glance. Uncluttered display. The outdoor temperature and humidity, and the indoor temperature and humidity (on the bottom in smaller lettering) are all displayed all the time.. > The only buttons are a Fahrenheit/Centigrade selector switch; a maximum button, and a minimum button. You can optionally use the minimum/maximum buttons to check the highest and lowest temperature and humidity, inside and out, since you last pushed the button. Just release the button and the display returns to the current readings. > The receiver (the display unit) sits at a slight angle (for optimal viewing) in a removable stand. The receiver unit also has a cutout on the back which allows it to be mounted on a nail-head or screw-head on the wall if you like---albeit you have to supply the nail or screw. You can carry it from room to room if you want. > You can hang the sender unit from a hook or a string from the "handle" on top. The also sender has a cutout on the back which allows it to be mounted on a nail-head or screw-head if you like---albeit you have to supply the nail or screw. It might take a bit of thought, effort, and your own hardware to mount it on a masonry wall. It will also stand up, or lie, on a table, etc. > The sending unit has a good range. I placed on a table in my screened patio, about 50' from the reciever. You could use it to monitor the temperature in another section of a large house, in your attic or basement, or in a neighboring building---such as a detached garage. CAVEATS > The display is LCD, and easy to read, but unlit. You need some light in order to read it. > Since there is no clock, it doesn't tell you when the highs or lows occurred. > The suggestion in the instruction manual to hang the sender unit by a string from a tree branch sounds like a very poor idea to me. If it swings around violently, it could be damaged by impact. Strings rot. > The instruction manual claims that the sender unit is waterproof. NOT so. Maybe the electronics are weather resistant, but the battery compartment is not. The sender is most likely to die by the battery contacts corroding. I suggest placing the sender unit in a location that is protected from directly sunlight, wind, rain, and high humidity. I suggest smearing the battery and battery compartment contacts with silicon grease to protect themPermatex 22058 Dielectric Tune-Up Grease, 3 oz. Tube > Finding a good place for the sender unit is by far the most difficult part of the installation procedure. Since the range is good, don't overlook the possibility of placing it inside an out-building such as a gazebo or tool shed. But don't protect it too much, because enclosed areas can become humid, which isn't good for electronics. The location should be "airy". > You can use any type of AA batteries. I suggest cheap ordinary alkalines. In very cold weather situations, you might want to put lithium batteries in the sender unit. Yeh, you can probably use rechargeables if you really want to, but doing so is rather pointless---even the best rechargeable will simply loose their charge in about 30 days---save your rechargeables for high-drain electronics, such as radios and toys. > Click on “Stoney” just below the product title to see my other reviews, or leave a comment to ask a question.