Yes the spec is 0.8mm but the weight varies depending on density of the paper. We loaded some sheets of Arches Torchon at 500g/m2 a long time ago into the roll feed slot. It went through was tight and had just a little touch on the very edge. So if the media is very flat, you can try and load thick heavyweight paper but just know that over 0.8mm will stress the machine in areas that may cause more than image quality problems.