Size:Large The Seresto Flea & Tick collar from Bayer offers a breakthrough of eight months of flea and tick protection for dogs or cats, setting it apart from conventional flea and tick collars. The Seresto collar offers the performance of a topical with the non-greasy convenience of an easy-to-use collar. Its sustained release technology means that the active ingredients are slowly and continuously released over 8 months. Kills fleas and continues to prevent re-infestations for up to 8 month. The Seresto collar also repels and kills ticks. The Seresto collar is also water resistant and remains effective following monthly bathing, occasional swimming (if swimming occurs more often than once a month, the duration is reduced to five months) or after exposure to rain or sunshine. This collar also features a release mechanism which in the unlikely event of a pet becoming trapped, the pet\'s own strength is sufficient to allow for a quick release.