The Gentle Spray Citronella Anti-Bark Collar helps train your dog by spraying a harmless burst of citronella spray to interrupt your dog's barking.  This spray works on their five senses; he hears it, sees it, feels it and most of all smells it.  The citronella is non harmful to humans or animals.  Dogs find it offensive enough to distract them and that's what interrupts the barking.  Use on any breed over 6 lbs and at least 6 months old.