UV light destroys germs' ability to reproduce and make you sick; The SteriPEN destroys over 99.9% of bacteria, viruses, and protozoaBattery Life: Up to 50 treatments per charge and 300 charge discharge cycles; This is equivalent to 15,000 litersSimple OLED display shows everything you need to know - treatment, lamp, and battery status; USB rechargeable from a computer, wall, or solar panel