A roller for a printer includes an outer tube and at least one inner tube. The inner tube is position within the outer tube. The outer tube extends in an axial direction from a first to a second end and the inner tube extends substantially parallel to the outer tube, defining an inter tubular space between the outer and the inner tube and an intra tubular space within the inner tube. The roller also includes a blocking element dividing the inter tubular space and the intra tubular space into a first part extending substantially from the first end to the blocking element and a second part extending substantially from the blocking element to the second end. A first and a second duct connects the first and second part of the inter tubular space with the second and first part, respectively, of the intra tubular space via the blocking element.