Proven to help reduce tension & conflict in multi-cat homes! Comfort Zone Multicat Diffuser with Feliway dispenses a drug-free, odorless vapor that mimics a cat’s natural calming pheromones. This vapor signals to your cat that the area is friendly and safe, reducing your cat’s need to spray and scratch. Easy to use, just screw the vial onto the diffuser unit and plug it into an electric socket! Leave the unit switched on continuously to keep your cats in harmony. Each diffuser refill covers an area up to 700 square feet. Avoid plugging your diffuser under shelves, behind doors or behind curtains, this will impair diffusion.