Material The training whistle is made of high quality stainless steel, sturdy and durable. The sound of the whistle is transmitted by ultrasonic waves and will not affect your dog"s hearing. It is very suitable for training dogs. . Adjustable Frequency Our ultrasonic dog whistle can reach a finer frequency range that humans can hardly hear, but it is very good for dogs and can train dogs to perform different actions. . Anti-lost Design Our dog whistle contains high quality lanyard. It can be hung around the neck and will not be easily lost due to its small size. . Easy Training Our dog whistle can reliably stop your dog from barking and help your pet learn commands and techniques. It is suitable for sports, hunting, herding, guide dogs and rescue dogs. . Wide Range of Applications This high quality small dog whistle is suitable for training small dogs, medium dogs and large dogs. You can always find the best frequency for your dog. . About Shipping: All items will be shipped within 3 business days after the payment is received. Most times you will receive them within 8-12 days then. The specific delivery time is depend on circumstances.Any questions, please feel free to contact us During the shopping process, if you have any questions, please feel free to consult us, we will reply you within 24 hours, wish you a happy shopping Thanks for your cooperation and we'll make you feel satisfied.