Contains (4) butane cartridge and (12) repellent mats for (48) hours of biting protection. Provides 15-foot by 15-foot Zone of Protection against bugs or 225 square feet when used with a ThermaCELL appliance or lantern. Effectively repels mosquitos, black flies and other flying, biting insects. Silent and virtually odor-free protection from biting insects. All ThermaCELL products come with a one year warranty.