Provides everything your ThermaCell Mosquito Repellent Unit needs to provide hours of spray-free, invisible, and odorless protection from mosquitoes. These mats emit an earth scent of musky dirt and decaying leaves to help mask human odors, making them perfect for hunters. Refill kit fits all ThermaCELL models. Each butane cartridge lasts up to 12 hours. Each mat provides up to 4 hours of protection. Refills can be stored for long periods of time, including between uses.