TBC Bark Contol Collar: Dog Bone Bark Controll Collar Stops Unwanted Barking with Ultrasonic Sound. One Size Fits All. Adjustable Stretch Collar. Trains Your Dog to Quit Bakings. High/Low Vibration Training Mode. Works on All Size & Breed of Dogs. Triggers Automatically By Bark Vibration. Safe, Humane, Effective. ONE SIZE FITS ALL WITH ADJUSTABLE STRETCH COLLAR TRAINS DOG TO QUIT BARKING TRIGGERS AUTOMATICALLY BY BARK VIBRATION