The Catchmaster Fly Trap features an enticing bait that can bring most hassle fly species. Simply add water to the bag and the attractant will dissolve and entice flies within minutes. Flies will enter the tote trap but will not have the ability to escape. The Catchmaster Fly Trap functions best when hung outside in the sun near decks, verandas, nearby trees, or when camping or enjoying other outdoor activites. Once the bag is filled with flies, it can be sealed and lost readily. A unique locking cap attribute ensures the bag contents will not spill or smell when not in use. Each bag includes a special soda cap and twist tie for hanging.