With its innovative delivery system, Seresto™ offers a breakthrough in flea and tick protection for dogs or cats for eight months. Seresto™ works similarly to a monthly topical, but as the active ingredients wear off over time, a new supply is continuously replenished in low concentrations. The active ingredients spread from the site of direct contact over the skin surface. Bayer's polymer matrix technology is designed to slowly and continuously release the active ingredients over eight months, a duration that makes it clearly different from other collars. Seresto is water resistant.