Company of Animals’ Pavlov No Bark Collar uses optional sound or vibration, not shock, to deter dogs from making unnecessary noise. While not recommended for puppies, or nervous or anxious dogs, the collar offers a smarter route to creating harmonious relationships between people and dogs. It has a high-tech micro-electromechanical systems (MEMS) microphone for filtered listening that only responds to dog barks but not to other sounds. It has seven automatic sensitivity levels: sound, vibration, or a combination of sound and vibration, each at one of three ascending intensities. The lightweight collar is padded and adjustable for comfort, and it is available in two sizes to fit any and all dogs.