The great outdoors is calling! Keep the mosquitoes away with Thermacell Repellent Devices and Refills. With 12 hours of protection you can camp hike hunt garden or simply sit on the patio without worrying about mosquitoes. Thermacell refills are compatible with all Thermacell devices - repellents lanterns and torches. While other repellents include chemicals put directly on skin Thermacell creates a 15ft by 15ft zone of protection around you. Thermacell repellent devices are powered by a fuel cartridge which provides the cordless portable heat that activates the devices. The heat generated by the cartridge is directed to a metal grill. A small mat saturated with repellent is inserted on top of the metal grill. Heat disperses the repellent from the mat into the air creating a protection zone. Turn it on... Mosquitoes GONE!