Commercial fly traps, using feeding and sex attractants or homemade fly traps using decaying meat or other foods, will capture large quantities of adult flies. However, these fly traps are limited in their usefulness and, when used alone, are not an effective method of controlling flies outside in livestock feedlots and premises over wide areas. Such traps sold commercially include Final Flight, Apache, Magnum, Big Stinky, Fly Terminator and others. Some Fly Relief Disposable Fly traps require additions of water only. Commercial traps usually consist of a 1 to 2-1/2 gallon break-resistant, plastic jug with a one-way giant-size baffle on top of the screw-type cap or lid for easy opening and closing. Some have a bright yellow top above the baffle as a visual fly attractant. A four ounce bottle of attractant is sufficient for two baitings in the Magnum Fly Trap or four baitings in the Fly Terminator trap. Some producers report success around calf pens and building perimeters when several traps are used collectively. In spite of enormous numbers of flies trapped, usually fly populations at the livestock facilities are not significantly reduced. Attractant traps placed between livestock housing and surrounding residences help reduce migration of flies to the residences. Many flies are trapped and even more remain in the area of the trap rather than continuing on to residences.