The Catchmaster Disposable Fly Trap is safe and easy to use with no chemicals or pesticides. The Catchmaster Fly Trap contains an attractive lure that will attract most nuisance fly species. Just add water to the bag and the attractant will dissolve and lure flies within minutes. Flies will enter the bag trap but will not be able to escape. The Catchmaster Fly Trap works best when hung outdoors in the sunlight near decks, patios, nearby trees, or when camping or enjoying other outdoor activities. Once the bag is full of flies, it can be sealed and discarded easily. A special locking cap feature ensures that the bag contents will not spill or emit unwanted odors. Each bag comes with a special pop cap and twist tie for hanging.