For the backyard and beyond, the Thermacell Patio Shield is easy to use and provides hours of scent-free, mess-free defence against mosquitoes. With no batteries or cords needed, the Patio Shield is convenient, portable mosquito protection, ideal for entertaining, gardening, at the cottage and more. Features a 15-foot zone of mosquito protection. Powered by a safe and compact 12-hour fuel cartridge.