Get effective protection from fleas, ticks and mosquitoes with K9 Advantix II from Bayer. This vet-recommended flea and tick control for large dogs between 21 and 55 pounds also kills and repels mosquitoes, a benefit not found in many other flea and tick products. Biting fleas, ticks and mosquitoes are not only a nuisance, they can spread disease and make your dog sick. Just one application of K9 Advantix II kills fleas, ticks and mosquitoes for 30 days. Evenly apply the entire contents of the K9 Advantix II tube to two to six spots (based on label directions and the dog's weight) on the top of the back from the shoulder to the base of the tail. At each spot, part the hair until the skin is visible. Place the tip of the tube on the skin and gently squeeze to expel a portion of the solution on the skin. The formula starts to work within 12 hours of application to kill fleas and keeps working for one month. Use year-round to help keep your dog protected from biting and infesting fleas. Do not use on cats; use only on dogs.