Brilliant product, our six month old border collie had discovered his voice and decided he needed to sound the alert about anything and everything and go on and on. We are on a bit of property with kangaroos rabbits and other distractions as well as (neighbours on the boundaries just far enough away to warrant his attention for their visitors etc. within a few days, after just a few corrections from the device, he ceased barking and reverted to low-level growls, and one bark to let us know to which we responded to reward his alert, and that's where it stopped. He has learned to simply let us know without needing to bark more than once or just growl. Didn't wear it after those few days he already corrects himself! Bloody fantastic!!!