This TIF TIF7201 Infrared thermometer is used to measure surface temperatures, the user aims the IR Thermometer at the target, presses a button, and reads the temperature display. The device has an optical lens that collects the radiated infrared energy from the object and focuses it on the detector. The detector converts the energy into an electrical signal that feets amplified and displayed as a temperature reading. An infrared thermometer measures temperature by sensing the magnitude of radiated energy at infrared frequencies. Using this data and the actual temperature of the detector, the thermometer calculates the temperature of the surface that emitted the energy.This product features SoC (System-on-a-Chip) Technology. Complete IR design incorporated on a single chip, creating compact and lightweight design. Innovative optical lens with high accuracy measurements over a wide temperature ranges with a 1:1 distance to spot ratio. Simply point at desired target and press the trigger for temperature reading. Visual low battery indicators and requires two inchAAA inch batteries which are included.