For use with FELIWAY diffusers, FELIWAY FRIENDS is a clinically proven solution to help cats live in harmony together at home. It works by mimicking unique calming messages that mother cats produce called pheromones. These messages help to reduce the frequency and intensity of fighting, tension and conflicts between cats in the home. Trusted by veterinarians and pet owners worldwide for over 25 years, more than 14 million cats have benefitted from FELIWAY cat pheromone products.