You can buy here: http://www.dogsilencerproguide.com/buy
BarkWise is a training device, and as with any training method, results may take anywhere from a couple days to a few weeks. This will depend on how quickly your dog takes to the training.
The collar is adjustable between 6 to 24 inches and the electronic unit is ergonomically designed to fit the contours of your dog’s neck. It only weighs 2.2 ounces so it won’t weigh your dog down.
If you need more reviews, I recommend you to read this article: http://dogbarkhelp.com/barkwise-best-vibration-bark-control-collar-reviews/