Black Flag Window Fly Trap, 4-Count, 24-Pack TRAPS FLYING INSECTS: Once they land, they never leave. DISCREET DESIGN: Transparent on sliding doors and windows. USE ANYWHERE: Adhere directly to any window, screen or sliding door anywhere flying insects are a problem. NO INSECTICIDES: Traps and stops flies, mosquitoes, gnats, moths and flying insects. GUARANTEED: Guaranteed to work or your money back. See product label for details.