Thermacell Fuel Cartridge Refills, 4 Pack are specially designed to keep your patio, lanterns, torches, and other fuel-powered Thermacell repellers running efficiently for extended periods without the hassle of cords or batteries. These refills enable your Thermacell mosquito repellent to create a 15-foot zone of protection by releasing a dirt-scented repellent that effectively drives mosquitoes away. Suitable for use both day and night, they provide maximum protection starting in just 15 minutes. This convenient pack includes four 12-hour fuel cartridges compatible with all fuel-powered Thermacell repellers.