Make fetch happen? with the Chuckit!? Whistle Flight?. This unique fetch toy creates a continuous whistle sound as it flies through the air, keeping your dog interested and engaged during fetch. Specially designed reeds create the whistle sound as the wind whips through the whistle chambers when thrown. The Whistle Flight is made of lightweight, flexible natural rubber that is gentle on your hands and your dog's mouth. The Whistle Flight was carefully engineered to securely house the whistles within the flyer to provide the best sound performance as well as keep your pet safe.