Modern dog training is now focused on reward rather than punishment, & for many animals a motivational, positive approach to training will achieve the desired outcome. However, just occasionally, an animal may misbehave to the extent that he places himself in danger, & a well-timed interruptive stimulus is required. The Dog Stop emits a high-pitched sound, distracting the dog & providing an opportunity to redirect his behaviour. 120 db screech Deters aggressive dogs Refills available