ChasDen

From web:

Displays indoor humidity and temperature
Displays Lo / OK / Hi comfort level icon
Keeps track of daily high/low temperature and humidity
Uses 1 AA (1.5V) alkaline battery (not included)
Main unit dimensions: 3" X 2 1/2" X 1 1/4" inches
Includes magnetic back for easy mounting to metal surfaces
Includes tilt stand for easy display on tables and desks

Also after you salt test it if its way off, some will be, take it back and get a new one. Explain that you tested it and it is off. If you do it within a few weeks of buying it they should exchange it. I have a bunch of them and have taken 2 back and they exchanged them no problem.

Chas