||The NOBARK collars senses a dog’s bark, it delivers a short, harmless, electronic stimulation. If the dog continues barking, the collar delivers another stimulation. A barking dog quickly discovers that the only way to avoid the correction is to be quiet. SportDOG Brand’s Perfect Bark® technology means the collar will never mistake anything for your dog’s bark except, well, your dog’s bark. The patented design requires both the sound of your dog’s bark and a tangible vibration from the bark to occur at the same time before it corrects your dog. Every other anti-bark system available triggers off one or the other, but not both. Hear the quiet?