The Bayer Seresto Flea & Tick Collar for Large Dogs over 18 pounds provides continuous 8-month flea and tick protection. Unlike oral flea and tick prevention products that require a bite, the Seresto collar repels fleas and ticks and kills through contact; no biting required. Frontline flea and tick treatment does not repel (based on label claims). Seresto dog collars are made with a long-lasting, 8-month formula for continuous release coverage over your dog’s skin and coat. Vet-recommended Seresto collars are water-resistant and remain effective after shampooing, swimming or exposure to rain or sunlight. (Dogs must not be bathed more than once per month. For dogs that swim once a month or more, the control duration is reduced to five months for flea control, and reduced to seven months for tick control.) This odorless, non-greasy collar is easy to apply and can be used alongside other identification or restraining collars without damaging them. Avoid the hassle of messy monthly treatments and get the effective protection of Seresto.