Calm Cat Comfort Diffuser, Reduce stress in your feline friend with FELIWAY® Optimum 30 Day Cat Calming Refill. Clinically proven to calm cats and kittens, our enhanced calming formula helps reduce common signs of stress. Veterinarian recommended, our pheromone diffuser provides a sense of comfort and relaxation for your beloved pet. Ease your cat's stress with continuous calming support for a happier home.