The Nubia Z20 is perhaps one of the more unique of all Snapdragon 855 Plus-powered flagships, as it has a 5.1-inch rear-facing display in addition to its 6.42-inch main screen. It has only been available in China since its launch; however, the OEM now has a global release date for this phone.
https://www.notebookcheck.net/The-dual-display-Nubia-Z20-flagship-will-be-released-to-the-US-market-in-October-2019.435170.0.html