Feliway friend diffuser contains a  synthetic pheromone that is  replicated from when the mother cat is nursing her kittens she produces naturally  a pheromone message to her kitten to help them feel safe and secure. This pheromone helps to create a harmonious bond between them. Feliway friends is a synthetic copy of this pheromone and has been clinically proven to help reduce tension and conflicts between cats in households with more than one cat.