Just add water and hang! RESCUE Disposable Fly Traps catch hundreds of the most annoying species. Includes a pesticide-free bait that flies find irresistible. Simply add water and hang outside. Lured by the scent, filth flies enter through the yellow top cap and drown in the water. Intended for outdoor use only. Features: • Attractant is contained within the bag — lasts for weeks! • Catches common filth and nuisance flies • Contains NO pesticides • Unique design prevents touching the pest — just toss away when full! • Holds up to 20,000 flies (yes, we counted them all!)