The ThermaCELL mosquito lantern is a dual product - use as a repellent and bright light simultaneously. Protects a 15' x 15' area against mosquitoes, black flies and other flying insects. 98% effective. Tested by the Department of Defense and is used by the U.S. Army. DEET-free, no open flame or messy wax. Alternative to smelly lotions and sprays. Silent, portable, and odor free. Includes 1 reusable lantern, 1 butane cartridge for 12 hours of protection, 2 insect repellent mats (each mat lasts up to 4 hours) and 4 "AA" batteries.