No noise for others: The dog's whistle can put out ultrasonic waves. The dog can hear the ultrasonic waves put out by this whistle, but people can't, so you don't have to worry about disturbing others when you whistle. . Dog whistle: The ultrasonic dog whistle will not harm the dog's hearing, so you can use this whistle to stop the dog from barking or train the dog to perform various actions. . Dog anti-lost whistle: High quality lanyard can help you wear it around your neck, you never worry about losing it. . Easy to use: The dog can clearly distinguish the ultrasonic waves put out by the dog whistle, and the owner can use the dog whistle to give different instructions to instruct the dog to do different actions. . Remark: This dog whistle will not make your dog immediately understand your instructions. You must train your dog with this whistle so that the dog can understand your commands. We recommend that you use motivational methods to train your dogs and make your pet a well-trained friend. .