What do you mean a "4 series"? An RTX 40 card?
It depends on the card you want, but it looks like it won't be able to fit the higher end models due to most of them being huge bricks of a thing.
EDIT: I'm also concerned about the cooling capabilities of the thing. The rear fan looks like a 92mm, if not an 80mm one. But that could just be a trickery of the images they used.