Seresto Flea and Tick Collar for Dogs Kills fleas within 24 hours and ticks within 48 hours after initial application. Re-infesting fleas are killed within two hours and reinfesting ticks on dogs are killed in as quickly as six hours. As the active ingredients wear off the dog. The flea and tick collar replenishes the hair and skin with a new supply of active ingredients, providing continuous protection against fleas and ticks for eight months. Repels ticks, preventing the tick from attaching and transmitting disease-causing organisms. Bayer's Polymer Matrix is designed to slowly and continuously release the active ingredients (imidacloprid and flumethrin) for 8 months. Includes optional reflector clips that can be attached to the collar for safety at night. Features: no need to remember monthly applications non-greasy odorless easy to use water-resistant* repels ticks on dogs and prevents diseases for use on dogs and puppies 7 weeks and older small dog collar has break-away notches for safety includes optional reflector clips for visibility at night Small Seresto Dog Collar is approx. 15 L (for dogs up to 18 lb) Large Seresto Dog Collar is approx. 27.5 L (for dogs over 18 lb) Active Ingredients: imidacloprid and flumethrin *Bathing or swimming more than once a month could result in a shorter active period for the collar.
