It's not necessarily your fault this thread became an unhelpful resource cluttered with garbage lol the diameters are in here too
MyTM came with one dome basket screen that fits the stock stem, I keep it in my short stem in front of the cooling unit screen, that is how I would load it for the most part, only about a cm deep. I posted links in the thread for two different mistvape screens, that are a bit more cup (vs dome) basket screens, one is shallow and one is deep. Those will also fit the stock quartz stems, and likely actually will fit the 18-mm WPA he sells too, since it supposedly fits the cooling unit?