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.
I really wanted these to work so I could run outdoors in the morning while the gyms are shut down. Unfortunately, they technology isn't strong enough for the Arizona dry heat and only lasts about 10 minutes into the run. Another item that missed the mark.