This insect growth regulator (Nylar) breaks the flea reproduction cycle by preventing flea larvae from turning into biting adults. Existing adult fleas are not affected. Safe for you and your pet. Mix 1 oz. per gallon of water and apply to areas which may harbor fleas, including carpets, furniture and pet sleeping areas. 1 oz. bottle treats 1,500 sq. ft. Works great outdoors, too!