The RESCUE! Fly Trap MAX captures and kills flies in a largest stand-alone, reusable container. Flies are drawn by our unmatched lure into the trap where they cannot escape. Our highest capacity trap is ideal for areas with maximum fly populations and can be reused again and again with available refills. Simply drop the water-soluble pouch into the trap, add water, and place or hang it outside at least 20 feet from where people gather to keep flies from bugging you. That's Smarter Pest Control.