Improving flatness is of critical importance in various industries that work with flat sheet or strip materials, such as printing. Flatness refers to any deviation from an ideal surface, so addressing this issue is necessary to ensuring the quality and functionality of finished products. There are various techniques employed to increase flatness, such as four-fold or four-high rolling. By using these sophisticated machines, manufacturers can achieve enhanced flatness control by precisely adjusting roll gaps, pressures and speeds during the rolling process. This can help reduce or even eliminate surface imperfections such as waves, wrinkles and other forms of unevenness, leading to flatter and more uniform sheet or strip materials. Improved flatness not only improves the aesthetics of finished products, but it can also contribute to higher performance, tighter tolerances, easier assembly processes and reduced handling and assembly times for downstream applications. It plays a crucial role in meeting modern manufacturing's stringent standards by producing top-quality materials with improved flatness.