Helps Reduce the Frequency and Intensity of Tension & Conflict Between Cats in Homes with Multiple Cats. Helps to create a calming environment. Start to See Results in a Week Veterinarian Recommended & Clinically Proven Contains 1 Diffuser and 1 48mL Refill. Refill lasts 30 days Use Comfort Zone Multicat together with Comfort Zone Feliway if the cats urine mark and scratch as well as have tension and conflict.