Rechargeable bark control collar for little dogs. Easy to use with no programming required. Great for reducing excessive barking or keeping your little dog quiet during times you need silence, the collar learns how much your dog barks and automatically adjusts using 1 of 15 levels of correction. This lightweight, waterproof collar fits pets 8 pounds and up and adjusts to fit neck sizes up to 23 inches. The collar uses a rechargeable battery and quickly recharges with the included USB (Universal Serial Bus) charger. Milder Levels of Static Correction - 15 levels of safe, gentle static correction levels that automatically adjust to help teach your sensitive, timid or small dog to stop excessive barking. Learns Your Dogs Bark - unique bark-sensing technology learns your dogs bark to prevent your dog from receiving a false correction from other dogs barks or outside noises. Waterproof Collar - The waterproof design allows you to bark train inside or outdoors. Rechargeable Battery - Battery life is up to 40 hours of use and quickly charges in 2 hours using the included USB charger. System Includes: Rechargeable bark collar & adjustable strap, test light tool, USB adaptor, and quick start guide.