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