SoothePaws Dog Calming Pheromone Refills Only | Choose 2/4/6 Pack (48 ml Each) | For SoothePaws Plug-In Diffuser | ~30 Days per Refill | Unscented & Drug-Free | Helps Reduce Barking, Chewing, Spraying & Restlessness | Covers up to ~700 sq ft per diffuser.