Are your cats Fighting, hissing or showing signs of tension and conflict? These behaviors can be signs that your cats are stressed or anxious. Cats are very territorial and adding another cat into a multi-cat home can cause the cats to feel threatened and stressed. Comfort Zone multi-cat diffusers dispense a drug-free vapor that mimics a cat's natural calming pheromones to create a calming environment which helps reduce your cats' Tension and conflict. These pheromones are diffused into the air which Signal to your cats that the area is safe, making your cats feel more comfortable. Use The Comfort Zone multi-cat diffuser kit if you see your cats Fighting or showing signs of tension and conflict. Plug in a diffuser into each room where your cats roam or spend the most time. Replace the refill every 30 days and the diffuser unit Every 12 months. Our products are SAFE and certified to U.L standards.