The Rechargeable Bark Control Collar from PetSafe discourages nuisance barking, whining, and whimpering. As your dog barks, the collar automatically adjusts to give a safe but annoying static correction. As your dog learns to bark less, correction levels are reduced. By utilizing unique bark-sensing technology, the collar provides the most reliable bark detection available. The collar only activates when your dog barks. It will not activate in response to another dog’s barking or other noises. Can be used with all dogs 8 pounds and over and with neck widths up to 28 inches.