Shatterproof and weather resistant. Select a location on a wall that is out of direct sunlight. Depending on surface material, you may need to pre drill a hole to install mounting screw. Installation should be made using a 1-1/2" #8 screw (not included). Factory calibrated to accurately measure temperatures from -60 degrees Fahrenheit to 120 degrees Fahrenheit (-50 to 50 degrees Celsius).