Small dogs have big voices, and they deserve tech that's tailored to their size. NanoBark 2.0 bark collar is purpose built for dogs with neck sizes 4 to 15 inches and helps stop nuisance barking so you can enjoy a peaceful home together. The slim, low-profile bark collar features a snug new fit with an updated design for extra flex and durability. Delivering the minimum effective level of correction for max results, it only responds to your dog's unique voice and tunes out the neighborhood noise. With 10 levels of auto-adjusting static correction, the bark collar helps prevent your dog from growing desensitized with patented Variable Pulse technology. The long-lasting battery stays charged for up to 7 days and the waterproof design means you can enjoy puddle play with ease.Proper fit of the collar is important. A collar worn for too long or made too tight on the pet's neck may cause skin damage ranging from redness to pressure ulcers. This condition is commonly known as bed sores. Avoid leaving the collar on a pet for more than 12 hours per day. When possible reposition the collar on the pet's neck every 1 to 2 hours. Regularly recheck the fit to prevent excessive pressure; follow the instructions in this manual. You may need to trim the hair in the area of the contact points. However, never shave the dog's neck; this may lead to a rash or infection. Never connect a leash to a collar with contact points. It will cause excessive pressure on the contact points. When connecting a leash to a separate collar, do not allow it to put pressure on the collar. Wash the dog's neck area and the contact points of the collar weekly with a damp cloth. Examine the contact area daily for signs of a rash or a sore. If a rash or sore is found, discontinue using this product until the skin has healed. If the condition persists beyond 48 hours, see your veterinarian. For additional information on bed sores and pressure necrosis, please visit our website. This product is only for use with healthy pets. If you're not certain that your pet is in good health, we recommend that you take your pet to a veterinarian before using this product. DO NOT attach a lead to the training collar. Not for use with aggressive dogs. Follow all safety instructions in the product manual.