Comfort Zone with Feliway 12-Pack Cat Diffuser Refills Vials, 48ml Convenient 12 pack Comfort Zone with Feliway helps end urine marking and scratching; includes a 48ml refill bottle (1.62 oz.) Mimics feline facial pheromone to reduce, or eliminate, stress-related behavior; clinically proven 95 percent effective Odorless and non-toxic; does not affect humans or pets; not a drug or tranquilizer; use for 90 days for best results