Comfort Zone relieves stress in cats and dogs by simulating naturally occurring pheromones that calm and reassure them in stressful situations. D.A.P. (Dog Appeasing Pheromone) mimics a natural reassuring pheromone produced by female dogs when nursing. Reduces or completely stops stress-related behavior including: barking, whimpering, chewing, urination, defecation and separation anxiety in dogs. Whereas Feliway mimics a natural comforting facial pheromone produced by cats. Reduces or completely stops stress-related behavior including: urine marking, vertical scratching, loss of appetite and adjusting to a new environment. Does not affect humans or other pets. Plug unit into electric socket. Vial lasts approximately 4 weeks. Covers 500 to 600 square foot.