K9 Advantix II - 4 PackK9 Advantix II 4 Pack Available in 0 10#, 11 20#, 21 55#, and over 55# K9 Advantix II is a topical prevention and treatment for ticks, fleas, mosquitos, biting flies and lice. Use monthly on dogs and puppies; available for dogs of all sizes. Repels and kills ticks for up to four weeks. Repels and kills fleas and kills fleas already on dogs within 12 hours. Prevents flea infestations, development of flea eggs, pupae and larvae for one month. Repels and