It can't print any engineering plastics.
I bought the QIDI Plus 4 based solely on the glowing YouTube reviews and the manufacturer's website. In reality, this printer has serious issues with automatic bed leveling( -1mm Z offset) when printing engineering-grade filaments at high temperatures (60°C+ chamber temperature and 100°C+ bed temperature). This is a widespread problem, and many users end up buying aftermarket modifications just to make the printer work properly in those conditions. I can't recommend buying it. I've owned the printer for three months, and during that time I've only managed to print a few PETG models. In my experience, my QIDI simply isn't capable of reliably printing anything more demanding.