Which (exact) plastic material is used for the Raspberry Pi 4 Case

[grobarko]

Hi,

I'd like to print on the plastic top of my Flirc Raspberry Pi 4 Case, but I get asked what is the exact plastic material used to make the top cover?

I can't seem to find that information anywhere.

Adding it to the FAQ might be helpful as well:
https://flirc.tv/more/raspberry-pi-4-case

P.S. And is the same plastic material used for the Flirc Rasperry Pi Zero Case as well?

Thanks,
V