Feature: 1. CORRECTS DOG BEHAVIOR: Dog barking collar corrects dog behaviors such as aggression, peering in the wrong places, unnecessary barking, etc. 2. RECHARGEABLE: Automatic bark collar uses a high capacity lithium battery, which can be recharged repeatedly and can get to 60 days long standby time. 3. SCOPE OF APPLICATION: Waterproof dog barking collar is suitable for all dogs, the diameter can be as large as 35cm and as small as 6cm. 4. WATERPROOF DESIGN: Automatic dog barking collar is waterproof and can be used safely in all weather conditions without fear of wind or rain. 5. SOFT AND COMFORTABLE: Waterproof dog barking collar is soft and comfortable for your dog to wear and will not hurt your dog's neck. Specification: Item Type: Automatic Dog Bark Collar Material: ABS Battery Type: Lithium Battery Size: Diameter: Approx. 6-35cm / 2.4-13.8in. Package List: 1 x Automatic Dog Bark Collar Note: 1. It is recommended to cut part of the long hair to ensure the efficiency of the product (for a small number of large dogs).2. Please allow some error due to manual measurement.