Below is a list of Kraft Tubes manufacturers from Wauwatosa, Wisconsin. Kraft tubes are cylindrical, hollow tube products made out of kraft paper, a type of cardboard composed of wood pulp and sulfate additives. Kraft paper is coarse and naturally a dark brown color, although it may be bleached to obtain a lighter surface color. Compared to other types of paper, kraft paper is stronger and able to withstand more pressure. However, it is also slightly more expensive than other types of papers and so is typically only used when a more durable material is needed.