Designed for the adventurer, the Thermacell Fuel-ZoneGuard Backpacker mosquito repellent is easy to use and provides hours of scent-free, mess-free mosquito defense up to 4.5 m (15 ft.). With no batteries or cords needed, it utilizes the same camping gas canisters (not included) that backpackers and campers commonly have in their bag already. It has a lightweight design (4 oz.) and compact size (97 mm x 50 mm x 67 mm) and provides dependable performance up to an elevation of 2,133 m (7,000 ft.). Fuel efficient with up to 90 hours of run time on a 4 oz. canister and up to 360 hours on a 16 oz. canister. Only compatible with valves designed to the EN417 specification.