The Thermacell Rechargeable Mosquito Repeller keeps mosquitoes away, without spray. It repels tough mosquitoes, including those that may transmit Encephalitis, Chikungunya, West Nile Virus, and Zika Virus. A rechargeable Li-Ion battery powers the heater. Heat activates the repellent. After 15 minutes, a mosquito protection zone is formed. Long lasting refills keep you protected and can be started and stopped many times. It operates with one simple touch of a button, making it one of the easiest Thermacell Repellers to use. It keeps mosquitoes away for up to 5.5 hours per charge and can operate continuously while charging. The charge indicator lets you know how much run time is left. The E-Series has been evaluated by the EPA for safety and effectiveness and provides a 20-foot zone of protection against mosquitoes. Unlike candles or torches, the advanced repellent is scent-free, and there’s no mess or smoke either. So, you can make the most of your time outside.