The Thermacell MR-300L Portable Mosquito Repellent effectively repels mosquitoes and other biting insects by creating a 15-foot zone of protection for bug-free comfort. Ideal for use while hiking, gardening, camping, fishing and hanging around the backyard, patio and balcony. Thermacell Repellents are approved by EPA (United States of America) and NEA (Singapore). 15-foot mosquito protection zone. Turn it on...Mosquitoes GONE!Portable and lightweightNo spray, no lotion and no mess. Scent-free and DEET-free.No open flame, no smoke, no candle waxPackage contains: 1 reusable MR-300L Black Repellent and 12 hours of refills - 3 repellent mats and 1 fuel cartridgeHow It Works:Thermacell mosquito repellent products are powered by a Thermacell fuel cartridge which directs heat to a small mat infused with the repellent Allethrin, a synthetic version of a naturally occurring repellent found in chrysanthemum flowers. Heat disperses the repellent creating the 15-foot zone of protection. For best results, use on days with mild or no wind (bugs are at their worst on these days), and allow 10-15 minutes to form a complete zone of protection around the unit. Thermacell products are safe, effective, and come with a 100% Satisfaction Guarantee.