Kills and repels fleas and ticks for 8 continuous months in one easy-to-use, non-greasy, odorless collar. 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. Seresto is an effective, reliable alternative to monthly flea and tick topicals that lasts for 8 months. These collars protect your dog or cat.