Feliway Optimum is a NEW feline pheromone complex to convey more impactful messages to calm cats better than ever. Supported by 20 years of feline stress expertise and over 25 clinical papers, NEW Feliway optimum contains the most advanced Feline Pheromones Complex, developed by the FELIWAY® research team. This new discovery delivers serenity messages, helping your cats feel comfortable and secure at home, providing reassurance and ensuring harmony between cats.