You two spend a lot of time together, but you may not notice a tiny flea or two at first. A single flea can bite your cat and feed for over three hours. Help prevent biting fleas on your cat with ADVANTAGE II. The active ingredients spread over the cat's skin surface and are then absorbed by invading fleas. ADVANTAGE II kills through contact. Fleas don't have to bite to die. Get ADVANTAGE II today. Don't give fleas a biting chance.