The Gearbest advertisement shows the US configuration as 120v and you've confirmed that the plug is US 110v. If you plug it into 220v (US typical) or higher, it's likely you'll let out the magic smoke. The Gearbest advertisement also notes that you should set the power supply to 120v. It is common for universal power supplies to have a 110/220v switch somewhere, and it is usually clearly marked. If you decide to change the plug to 220v, you would still have to check the switch to ensure that the seller hasn't already moved it to 110v for USA use. 110v/120v used interchangeably as well as 220v/240v.