Feliway is a synthetic copy of the facial pheromone cats leave when they rub their cheeks on items in the home. This is a comforting pheromone which cats use to mark their home environment as safe. Developed after years of veterinary research, Feliway mimics this pheromone and is scientifically proven to help stop or prevent unwanted behaviours in cats. FELIWAY Plug-in Diffuser & Refill 48ml (only 1 refill in packet)