Seresto is an effective, reliable alternative to monthly flea and tick topicals. This dual-action collar repels and kills fleas & ticks for 8 consecutive months. If a flea or tick is repelled, it cannot attach and transmit disease-causing organisms. Seresto is a flea and tick collar for dogs and cats that uses exciting, innovative technology to release the active ingredients in controlled doses over an extended period of time. This means effective long-term flea and tick control without the inconvenience of monthly applications. Seresto protects your pet from fleas, flea eggs, flea larvae, ticks, as well as sarcoptic mange on dogs without odor or mess. It is available in three formulations for Small Dogs up to 18 lbs, Large Dogs over 18 lbs, and Cats of all weights.