Frontline Plus provides your dog with the most complete spot-on flea and tick protection available. In addition to killing 98-100% of adult fleas on your dog within 24 hours, Frontline Plus contains a special ingredient that kills flea eggs and larvae, along with keeping all stages of fleas from developing. Frontline Plus kills all stages of 4 major ticks including those that may transmit Lyme Disease and Rocky Mountain Spotted Fever. It's completely waterproof. Frontline plus is suitable for dogs over 8 weeks of age.