For today's investments, quick pay-back is becoming more important than ever before. The market increasingly demands the shortest possible delivery times and correspondingly greater flexibility of production. Minimal shutdown times as well as a fast start-up curve during start-up or restarting of the plant have become an absolute necessity today. A new plant concept is illustrated by the extension project of an existing Steckel mill with three finishing stands in tandem arrangement to increase its annual production. Furthermore, the quality of the products will be clearly enhanced thanks to the modified process and the selected technology. In order to implement all this with the highest possible commercial benefit, a revolutionary revamping concept, which reduces the mill shutdown period to a minimum, is introduced to the market. The so-called “add on products” have been developed to generate the highest possible benefit in existing facilities with limited expense and effort. Highlights include the differential tension looper and the tensiometer looper, the compact cooling system, edge masking as well as the on-line polisher.