Seresto Flea and Tick Collar for Cats 10 weeks of age and older kills and repels fleas and ticks for 8 continuous months. Seresto collar flea and tick prevention for cats, works through contact, so fleas and ticks don't have to bite your cat to die. Frontline flea and tick treatment does not repel (based on label claims). The Seresto flea and tick collar contains the active ingredients imidacloprid and flumethrin, which are slowly and continuously released in low concentrations, spreading from head to toes, even the tail, over your cat’s coat and skin. The odorless, non greasy collar is easy to put on, and it can be used alongside other identification collars. Avoid the hassle of messy monthly applications and get effective protection from Seresto. Also available: Seresto flea and tick collar for dogs.