Wilson®One Shot® Fly Ribbon is a non-toxic sticky trap that can be hung indoors or outdoors to trap flying insects. Flies are sensitive to light, temperature and humidity. If no insects are caught within 2 or 3 days, switch ribbon to another location (further from or closer to another window, etc.). Use anywhere flying insects are a problem, such as in cottages, homes, garages, barns, on patios, porches, decks, etc. This product does not emit any vapours, fumes or odours. Does not use any chemicals. Each pack includes 4 ribbons. Get rid of flies effectively with Wilson® One Shot® Fly Ribbon.