Ditch the Bug Spray For the backyard and beyond Thermacell Refills keep your Patio Shields Lanterns Torches and other fuel-powered Thermacell Repellers fueled for the long haul with no batteries or cords required. Always be prepared by keeping extra cartridges and mats in your tent backpack garage or tackle box for whenever you need them. With a 15-foot by 15-foot zone of protection you can camp hike hunt garden or simply sit on the patio without worrying about mosquitoes or pesky insects. Thermacell repellent devices are powered by fuel cartridges which provide cordless and portable heat. This heat disperses a small mosquito repellent saturated mat into the air and eclipses you with a powerful zone of protection from mosquitoes. Turn it on... Mosquitoes GONE!