The Primo Instant Read Thermometer will accurately measure the internal temperature of your food in as little as 2 to 3 seconds. The large and easy to read display shows Fahrenheit or Celsius and the display can rotate 180 degrees and switch between a left and right hand display. This thermometer can read as low was -40 F and and high as 660 F. The backlit display makes grilling easy at night. The probe automatically powers on when it is open, and powers down when closed. While getting a temperature reading of your food, if you press the hold button, it will lock the temperature reading on the display. This thermometer can also be calibrated by inserting the probe into a known water temperature like ice water or boiling water. It also has a low battery indicator. Two AAA batteries are included.