Features: 1.With 7-level sensitivity adjustment, it is an efficient behavior modification tool that will help you train your dog to bark less. 2.Can be easily charged with the USB cable. 3.It's tinier, lighter and comfortable for dogs. 4.Whether your dog is a small dog or a large dog our adjustable dog bark collar can fit them just fine. 5.The collar is waterproof, no worry to use it even in rainy day. Specification: Material: Plastic+Nylon Size: Approx.6.7*4*3cm /2.64*1.57*1.18in Battery: Built-in 300mA lithium battery Charging Method: USB charging Adjustable Diameter Range: 6-36cm Voltage: DC 5V Pet Size: All Size Weight: 78g Color: Blue Package List: 1* Dog Training Collar 1* USB Cable 1* Manual Notice: If the dog's hair is too long, it is recommended to cut it short to avoid affecting the vibration of the product. Please allow 1-3cm error due to manual measurement and make sure you do not mind before ordering. Please understand that colors may exist chromatic aberration as the different placement of pictures.