The IDEAL Electrical 61827 Single Laser Targeting Infrared Thermometer is a non-contact temperature sensing meter. Its single laser defines the center of the area whose temperature will be measured. The IRT measures temperatures from -4° to 752°F (-20° to 400°C). The LCD backlit display is automatically illuminated when the trigger is pulled and allows working in poor or zero lighting conditions. The single laser targeting system is also activated when the trigger is pulled. 61-827 uses a single red laser located above the IR sensor to locate the center of the area being measured. The meter constantly updates the temperature measurement when pulling the trigger. 61-827 also has selectable Fahrenheit and Celsius measurement, Auto Power Off, and comes with 2 1.5V AAA batteries.