It obtains a reading in as little as six seconds by simply touching the patient's forehead, making it excellent for use on sleeping babies and children. Since it doesn't use probe covers, this Adtemp 427 temple touch thermometer eliminates the risk of cross-contamination. Once it obtains a reading, it makes an audible tone to let you know it has recorded a temperature. This Adtemp temple touch thermometer has a large LCD display to easily read the temperature. It's powered by two AAA batteries (included) and its auto off function conserves battery life. The display gives readings in either Fahrenheit or Celsius for easy conversion between the two scales. This ADC temple touch thermometer also displays its last reading so that you can compare and contrast it with your current reading. Measuring just 4.7 inches x 1.17 inches x 1 inches, it's easily portable.