When I received this item it did not work as advertised. I contacted Vevor and received a prompt reply with instructions to charge the head unit completely (I had already done this). Next they wanted a visor of the issue, but it had to be a small number of bytes, returns requiring a quick vid. Next out had to be uploaded to a certain site. This was not easy (to me) and made me question Vevor's sincerity. In their defense, I received quick replies to all my questions during this process. Ultimately, Vevor sent me a new unit which works perfectly. I will buy from Vevor again.