The Adams Plus Flea & Tick Collar for Cats kills adult fleas, ticks, flea eggs and flea larvae for up to 7 months. The IGR ingredients are distributed through the coat and skin to cover the entire body. For continuous flea and tick protection under normal conditions replace the collar every 7 months. Wetting will not impair the collar’s effectiveness. Do not use on kittens younger than 12 weeks of age.