Acme 576 Shepherds Lip Working Dog Whistle The Acme No 576 Working Dog Whistle, also known as the Shepherd's Lip Whistle, was made famous by the television program, One Man and His Dog. This professional model enables the dog trainer to create a crescendo of sound in tremendous variety. There are many dog trainers who consider this to be the ultimate in-tune communication with your dog. Available in a wide variety of colours. Takes practise to get to work {How To Use} Shepherds Whistle Instructions. 1. Place whistle in mouth with the curved open edge facing outwards resting on your tongue. 2. Hold in the mouth in such a way as to create a gap underneath the whistle. The back of the whistle will sit on the back of the tongue. 3. Blow and by varying the blow, you will create different sounds. 4. To create an even wider range of sounds, move the tongue up and down reducing and widening the gap underneath the whistle. N.B. if you place your tongue against the lower hole you will silence the whistle. It doesn?t matter which way up the whistle is placed. This whistle does require a few practice blows before you get a sound, but once one sound is achieved, it is plain sailing or whistling.