Cardboard is a material made of a fluted corrugated sheet and one or two sheets of flat linerboards. Cardboard was invented more than a hundred years ago. It is a low-cost, strong and light-weight material that is easy to process. Also, it is an environment-friendly material as over 80% of cardboard sheets can be recycled. Cardboard is widely used in laser engraving and DIY projects, and STEAM education workshops. • Circular barcode labels are attached to the products. Laserbox can automatically identify the barcodes, allowing users to skip manual setup. • Flat, high-density, high-strength, easy to fold, low-cost, environment-friendly • The cardboard can be used in model-making, DIY, laser engraving projects and other types of crafts. 45 sheets in a box. Product dimensions: 296*210*3.5 mm