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 product finally arrived but was more than 3 weeks later than estimated arrival date. Be careful if you're not sure about the product, refund/return will cost you more than product itself as it ships from China. But manufacturer was helpful.