The Triplett UVLT150 UV A/B Light Meter measures Ultraviolet A and B rays which are naturally occurring in sunlight or generated in multiple industrial and medical applications. Some of the applications includes photochemical matching, photo resist exposure, curing of inks/adhesives/coatings, monitoring blue light radiation hazards in welding, UV sterilization, Virology, microbial genetics, DNA research, and others. Readings are displayed on the 3-3/4 Digit backlit LCD in µW/cm² or mW/cm² units of measure. Users can use the Zero button to zero out the display for accurate measurements. Data Hold freezes readings on the display for easy viewing, low battery indicator lets users know that its time to replace the batteries, Auto power off with disable conserves battery life.