THREE LAYER STRUCTURE - All corrugated cardboard sheets adopt a 3 layer ultra rigid structure, which gives it excellent durability and strength. It is definitely your best choice for packaging and transportation. SIZE - Each cardboard pad has a size of 297 x 210mm/A4, with a thickness of 3mm. The surface of the cardboard sheet is flat and smooth, and the size is sufficient to meet your printing, painting, or writing needs. ECONOMICAL - This package contains 40 cardboard sheets, which makes it ideal for those who need a lot of cardboard. In addition, they are relatively inexpensive, making them a very economical choice. VERSATILE USE - These flat cardboard sheets are suitable for a wide range of applications, including DIY projects, crafting, and more. They can be easily cut and shaped to meet your specific needs. WORRY-FREE PURCHASE - If you have any dissatisfaction or feedback with a4 corrugated cardboard sheets after receiving the product, you can contact us. We are dedicated to providing you a satisfactory shopping satisfaction.