It's a HP Envy.
TBH, I hadn't realised it had also chosen to encrypt the inserted SD card when I added it.
I would install from a USB to another USB, but the Debian Live USB stick doesn't recognise anything else that I plug into the laptop, so I can't go USB to USB, hence the need to use windows.
No preventing me from formatting, but from resizing the disk so I can make space for the linux on the internal SSD.