The Thermacell MR450 Mosquito Repeller effectively repels mosquitoes and other biting insects by creating a 15 x 15-foot zone of protection for bug-free comfort. Built to be tough enough for any adventure, the MR450 will quickly become an essential piece of gear. Thermacell Repellers have been evaluated by the EPA for safety and effectiveness. FeaturesRubber armoredZone of Protection indicatorAccessory mounting systemRe engineered grillErgonomic designRepels mosquitoes, black flies and other flying insectsThermacell products create a 15' x 15' zone of protection in minutes that lasts for hoursIncludes three original repellent mats lasting four hours each, providing 12 total hours of repellencyUses Thermacell butane cartridge refills for mosquito repellent function; each cartridge lasts up to 12 hoursSilent, virtually odor-free, no open flame