Effective for up to 4 weeks with a range of 50 to 100 yards. That's powerful. Strongly effective in decreasing the fly problem of an area, even pesticide resistant flies. NO toxins, NO poisons, NO insecticides. Catches up to 20,000 flies in each trap and up to ten times faster than other traps. Maintenance free and completely disposable. Nothing to clean up. Highly effective even on fruit flies. Used extensively in the pest control industry. A farmers true friend for use in the poultry industry, on dairy farms, stables, livestock ranches, feed lots, kennels, waste products. Also restaurant dumpsters or anywhere that flies are a problem. Available also for home use.