To calculate the overall star rating and percentage breakdown by star, we don’t use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyses reviews to verify trustworthiness.
The medium collar I purchased is falling apart the foam padding inside the collar is breaking off along one side. Have only used about 1 month, very disappointing, the one I had previously lasted 2 years and withstood machine washings many, many times.