Product description The first ever \'Silent\' Dog Whistle. Adjustable frequency to suit your dogs hearing. Each whistle is individually tested and guaranteed. Designed for your dog's sesitive hearing by Acme the inventors of the Silent Dog Whistle. Acme is relied on by professional trainers world wide for over 130 years. Made in United Kingdom. 
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Instructions on back of package.
Acme Silent Dog Whistle from Markwort
The Acme Silent Dog Training Whistle provides an extremely high pitched, adjustable sound that dogs can hear--and that is almost inaudible to humans. Developed for hunting dogs, the training whistle can be heard by dogs from up to 400 yards away (direction and strength of wind may affect the distance). This precision whistle allows you to set the ideal pitch with a pitch register. Instructions come included on the back of the package.
Features:
- High pitch can be heard by dogs not people
- 400 yard range depending on conditions
- Pitch register for easy adjustments
- Measures four inches long
