For the backyard and beyond, Thermacell rechargeable repellent refills keep your devices running for the long haul. Featuring a 6 m (20 ft.) zone of repellency against mosquitoes, the largest zone yet. Always be prepared by keeping extra cartridges in your tent, backpack, garage, or tackle box. Portable and air travel-friendly. (Compatible with Thermacell rechargeable repellers only.)