Carpenters nail bars. Dogyu has built a reputation by manufacturing and providing the World with precision hand tools and instruments since 1908. Tools must be designed to reflect not only the wishes of the users, but also the intentions of the makers. A hand tool is a reflection of human history. Tools were produced as people learned to make use of nature. Easy on people, in tune with nature, that is the origin of the tool. As time progresses, tools keep evolving.