Spiral binders made of Colorspan 355 g/m² - A4 This spiral binder is made from Colorspan cardboard, a cardboard of unique quality, homogeneous and colored, without coating and without the addition of plastic materials. It is more durable than all other everyday use cardboards. The spiral binders are easy and safe to use. They allow for secure storage of punched documents. The printed cover allows for optimal labeling of the contents. For perforated A4 documents, with a spacing of 80 mm, for up to 300 sheets in A4 (80 g) FSC certified. The spiral binder is manufactured in our plant in Germany.