Johnson's 4fleas Spot-On for Cats and Kittens is a fast acting Spot-On, suitable for pets over 8 weeks of age and weighing less than 4kg. This Premium Veterinary Strength Dual Action Spot-On kills fleas on contact and gives up to 4 weeks protection. Stops fleas biting in 3-5 minutes, and kills flea larvae within 20 minutes of contact in the area around your pet, including bedding, resting areas, etc. Kills 98-100% of fleas within 12 hours.