Shepherd's Whistle

This professional model enables the trainer to create a crescendo of sound in tremendous variety. There are many dog trainers who consider this to be the ultimate in-tune communication with your dog. You can communicate a faster and wider array of conversational commands with an animal than you can with your voice. The whistle can be heard up to a mile away and in all weather conditions, versus your voice, which is generally only effective up to a quarter mile at full volume.

Also great for teaching a horse to come to a whistle in the paddock.

Made in England by the ACME whistle folks.