ACME Silent Whistle No. 535 The 'Silent' Dog For All Breeds Also Animal Training with Dolphins Humans (Almost) Not Audible

High frequency: the whistle works in a frequency range of 5400 - 22800 Hz, with some sounds almost inaudible to humans, but particularly clear to dogs, dolphins and other animals. Adjustable: the whistle tones are adjustable and can then be fixed. They range from a sound that is little more than a beep for humans to a bright tone that we humans can clearly recognize. WIDE RANGE: the sounds of the whistle can bridge an amazing distance of up to 1.5 km. The animals can easily perceive the whistle even at a long distance and despite loud ambient noise. With lid: this model comes with a mouthpiece and a separate lid that can be placed over the pipe. The lid is attached with a small chain, so it cannot be lost and always stays on the whistle. Unique design: the eye-catching design of the whistle is a real eye-catcher. It is made of brass and available in various overlays that give each piece an individual, characteristic charm.