A dog, man's best friend.
It was a long way from the wild wolf to the pampered pet dog of these days.
Remember, even your tiny terrier is a descendant of this wild and free beasts ... show some respect and treat them as friends, too!
In the sprit of this, the whistle is annoyingly loud to both: dogs and humans. So, this is no "silent" dog whistle.
The whistle was inspired by the antique whistles made in england in the late 1800s. If you want to know more about great whistlemakers like J. Hudson or T. Yates, check out one of this sites: