The Solarmeter Model 6.5 UV Index Meter provides instantaneous UV index measurement and is also used for UV index comparison, monitoring reptile lamp intensity and aging, monitoring UV lamp intensity and aging, and UV index tracking over time. The simple, one-hand operation of this device makes it easy to monitor UV light intensity levels to decide when it's best to do outdoor activities. It's an essential tool that helps anyone who enjoys sports, running, swimming, surfing, and hiking to check UV exposure and stay safe. Our light meter comes with a NIST Traceable Calibration Reference Card and runs on a single 9-volt DC Battery, which is included for your convenience. The Solarmeter Model 6.5 is not a medical instrument, but rather an affordable scientific instrument designed to help you avoid sunburn by providing an instantaneous UV index value.