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.
Don't buy this product .the product is very bad.my neck get injured .the customer service is very bad one of the Amazon customer executive name Lakshya talk very rudely when I ask for to return . don't buy please