The Raid Fly Trap, traps and kills common flies and many other flying insects with no poisons or insecticides. Our trap utilizes a proven food based lure to attract flies. The patented entry holes entice the pests to enter the trap. Once the pests enter, they are unable to escape, then drown. The trap can be used effectively for both indoor and outdoor living spaces. Attracts, Traps & Kills Flies & Flying Insects. For Indoor or Outdoor Use.