pfff you are right mine is 5.5…not sure why I put down 7". I wanted the 5.5" because I wanted it to as close to the same height as possible as nearby devices and when I went to their website I grabbed the correct model number but not the right specs because I had at least 15 tabs open and made an error.
Those ali-express products should be sold by a seller for sunworld technology limited. This is the only seller that sells their own specific product that they make. All other sellers are just buying their products and re-selling. They are more specifically the manufacturer to the owner company of Port World solutions (also out of China). They make decent products.
Here is their webpage: Products | Smart Home Touch Panels, POS Digital Signage,ODM,OEM,B2B | Portworld Factory
I believe they are all POE, there is an 8" version that is also POE and can go into a standard round electrical box (as long as it only has low voltage or ethernet supplied to it. The model number for the 8" version is YC-SM08P and show on ali as 125$ a piece. I bought from the same company and the guy literally sent videos for everything I wanted. I specifically wanted proof that it could run download and run HA app and set to wall panel. He recorded a video of the download and opening and running the app. I was sold. Within a couple hours after request, he dug out all data for the rs485 ports and sent me their custom API that allows you to talk to the ports. While I have 0 android app building skills, I was impressed because if I did, it would have helped me greatly.