Mosquito repellent butane refill. Thermacell's award-winning technology keeps mosquitoes away by creating a 15-foot protection zone around you. The proprietary formula precisely targets mosquito sensors, driving them away. With consistent protection that doesn't weaken over time, Thermacell helps you live your best outside life without the use of bug sprays or lotions on your skin. Always be prepared by keeping extra cartridges and mats in your tent, backpack, garage, or tackle box ready when you need it.This refill pack is compatible with all Thermacell fuel-powered repellers (except the Backpacker). Comes with 48 hours of fuel.