Bayer Advantage II Flea Prevention for Cats Veterinarian-recommended monthly ea treatment for cats Odorless Kills through contact. No biting required Easy to apply ea prevention for cats Starts working within 12 hours, keeps working for 30 days Brought to you by Bayer Packaging may vary Whether your cat is a winter sunspot stealer or a summer backyard explorer, an indoor sun seeker or an outdoor enthusiast, choose Advantage II to help keep fleas from interrupting their favorite activities year-round.