Check the listing for details. Feliway Plug-in Diffuser + 48ml Refil. Condition: New. Listed at 25.00 USD. The Feliway Plug-in Diffuser + 48ml Refill is a pet accessory designed for cats. This diffuser kit by Feliway helps reduce stress and anxiety in cats by providing a calming scent through the use of pheromone sprays. The included 48ml refill ensures that the diffuser can continue to provide this soothing aroma for an extended period of time, creating a peaceful environment for your feline companion.