This flea and tick prevention collar by Bayer kills and repels fleas and ticks for 8 continuous months in one easy-to-use, non-greasy, odorless collar. Flea collar that quickly kills fleas within 24 hours of initial application. Reinfesting fleas are killed within 2 hours. Prevents tick infestations within 48 hours after application. Kills and repels reinfesting ticks in as quickly as 6 hours.