The 3.3.3. Freewheel was the first product manufactured and marketed by Shimano Iron Works, the predecessor of Shimano Inc. At that time, the freewheel, which could be said to have been the core component of a bicycle, was considered particularly difficult to produce even with technological capabilities in the bicycle industry, which was developing in Sakai. Aiming to produce high-quality products that did not fall short in comparison to imports, Shimano continued research and made improvements, and successfully established a production system. As a result, a freewheel with the trademark “3.3.3.” inscribed on it, which can be said to be the origin of Shimano, was completed.