Thermacell started with a mission to find a better way to fight mosquitoes, and we figured it out. With a full line of rechargeable and portable repellers, we're winning the battle against bothersome buzzing and expanding to protect against other insects like black flies and no-see-ums, sometimes called gnats. Until now, sprays, lotions, torches, DEET and citronella have been the only options for fighting mosquitoes and pesky insects. Enter Thermacell. For the backyard and beyond, Thermacell Multi Insect Repellent Refills keep your Patio Shields, Lanterns, and Portable Repellers running for the long haul, no batteries or cords needed. Compatible with all fuel-powered Thermacell repellers (except the Backpacker). The first and only EPA registered area repellent for black flies and no-see-ums, these refills protect from mosquitoes, black flies and no-see-ums (gnats). Not for the common house fly. Always be prepared by keeping an extra cartridge and mat in your tent, backpack, garage, or tackle box, ready when you need it.