Thermacell Patio Shield Mosquito Repeller in Black/Graphite color, is easy to use and provides hours of scent-free, mess-free defense against mosquitoes. It features a 15-foot zone of mosquito protection and is powered by a safe and compact 12-hour fuel cartridge. With no batteries or cords needed, the Patio Shield is convenient, portable mosquito protection, ideal for entertaining, gardening, poolside, and more. For Single 12 Hour Refill Use TV# 876557, For Other Refill Cartridges Use TV#'s 672412 or 217236.