998e2bac_n_of_No_Pull_Dog_Training_Aids__2
[0] Noise Maker that Attaches to the Leash [1] Wonder Whistle [3] We like to use this product as a reminder to the *human* to stop walking so that the dog is not successful at moving you, which would reinforce pulling! [4] Dogs don't generally find the whistle to be much of a deterrent. Dogs that are very sounds sensitive may find the whistle frightening [5] 6 out of 10 [2] 
When the dog pulls it activates a whistle which discourages the dog from pulling.
Comparison of No-Pull Dog Training Aids
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