As described this is a Mk 46 Iron Man helmtet split up into 9 pieces, the really small mouthpiece teeth section of the helmet may need to be printed with a resin printer depending on the printer.

The Blender file is a low poly and not scaled version to save on space but has been ndesigned to be high res if you use Subdivision Surface Modifier so you can choose how smooth you want it.

I can provide smoothed versions in .stl .obj and .fbx if it is required