Keep your cat feeling right at home with the Feliway Cat Diffuser Refill. When a cat feels comfortable in their environment, they rub their cheeks against objects like the wall or furniture, leaving a facial pheromone behind. This refill is designed to work with the Feliway Diffuser, and itOs a synthetic copy of their own facial pheromone. By filling the air with a scent that mimics their own natural pheromones, this diffuser refill creates a state of familiarity and security. This makes it a great tool to help cats cope with challenging situations, and to help prevent or reduce stress caused by a change in their environment.Refill works with the Feliway Cat Diffuser plug-in. Easily pop the old one out and replace with the new one.Mimics catOs natural facial pheromones, which creates a state of familiarity and security.May help with stressful situations like a new pet, moving to a new home, visitors or even rearranging the furniture.Veterinarian recommended and clinically proven to start seeing results within the first week.For best results plug diffuser in room where cats spend most of their time together.