The ROG Phone 5 Ultimate is the spearhead of the series and the only model that can draw on 18 GB of working memory. The monochrome Vision display on the back is supposed to exude a classy flair, and the sensor keys on the back expand the gaming controls.
https://www.notebookcheck.net/Asus-ROG-Phone-5-Ultimate-review-The-collector-s-item-among-gaming-smartphones.562986.0.html