RESCUE! Big Bag Outdoor Disposable Fly Trap has twice the capacity of our Disposable Fly Trap. Contains a fast-acting fly attractant that starts working as soon as you add water. Flies find it fast! The RESCUE! Big Bag Outdoor Fly Trap catches flies in bulk in areas with large fly populations such as barns stables and animal pens. Flies are lured by the scent; flies enter in through the yellow top cap but can t get out. Never touch the bait or flies just dispose and hang a new one. Made of high-performance resin. 1 Pack