Train your dog effectively with the Unipet Silent Metal Dog Whistle. This silent whistle emits ultrasonic frequencies that are inaudible to humans but can be easily heard by dogs, making it an ideal training tool for obedience and recall commands. Its compact size and durable metal construction make it perfect for use during outdoor activities or training sessions. Build a stronger bond with your furry friend with the help of this silent whistle. Train your dog effectively with the Unipet Silent Metal Dog Whistle. Emits ultrasonic frequencies that are inaudible to humans but easily heard by dogs. Compact size and durable metal construction for outdoor training sessions.