Virbac Knockout E.S. Spray aerosol spray that kills adult fleas and ticks and prevents flea infestation for up to 7 months.No mess; Leaves no unpleasant odor or sticky mess and, when used as directed, does not stain furnishings. Reaches fleas hidden in carpets, rugs, drapes, upholstery, pet bedding and floor cracks. One 16 oz. can covers 2,100 square feet. Can prevent flea infestations from developing for up to 7 months.