CEVA Feliway Pheromone Diffuser for Cats (Diffuser with Vial Set)CEVA Feliway Pheromone Diffuser for Cats Cats communicate through natural messages released in the air (scientifically called pheromones). These feline odourless messages are only perceived by other cats, not by people nor dogs. FELIWAY works by sending natural reassuring messages to cats and helps them feel safe, calm and secure in the environment where it is applied. Aids in the management of stress behaviours such as: Urination in unsual places