You can get the accurate temperature reading from this large LCD Display in Fahrenheit or Celsius degree.

For the first use:

Open the batter cover with a coin or similar tool, please DON'T FORGET to remove the insulation spacer (white color and round shape), and then put the button cells back (make sure the rubber seal in position and correct battery polarity), tighten the battery cover and the thermometer will turn on AUTOMATICALLY.

Remember to clean the thermometer with dry cloth after each use, it will turn off AUTOMATICALLY after around 30 minutes when placed still (for energy-saving).