The secret is the lobster trap design and the non-toxic, bio-degradable bait that the flies can't resist. Just add the bait, pour in water and hang it. That’s it! Within minutes Flies Away starts to put out a scent that drives flies crazy and can catch and eliminate over 20,000 flies. Use it outside to keep pesky flies from coming inside, hang by the garbage and your family gatherings will be fly free.