Features:
100% Brand New.
Colour: Chrome Silver
Material: Chrome Plated Brass
Key ring loop included
1 Whistle
Part 1: Ultrasonic. Inaudible to the Human Ear, but very audible to the dog.
Part 2: Audible Element, this can be heard by the Human Ear, which helps the owner to distinguish long and/or short whistles to train their dog.
Adjustable pitch - simply tighten or loosen the screw to work out your dogs frequency It should be noted that this whistle is audible to the human ear, essential for gauging its efficiency.
Notes:
1 inch = 2.54 cm
1. Please allow 0.5-1CM differs due to manual measurement.
2. Real color may slightly different from pictures due to computer screen's resolution, brightness, contrast etc. 
Hope understanding. Have a nice shopping day!