Safer Brand Victor M382 Fly Magnet Trap, 1 Gallon with Bait Attractant lures them in, they can't escape and they drown Baited system effectiveness is not diminished with time. Bait will attract a broad range of species, including house and blowflies Traps are re-usable. Once filled with flies, dump contents, re-bait, add water and do it again! Replacements baits are available Bait is completely non-toxic and made of dehydrated food-grade products; Empty bait into trap then add water White color and diamond-shaped lid designed to attract more flies