Radius 10-90 Sheet Dimensions: 170 x 180 x 1.0 With Ink Edge, The ruler has a step so that ink doesnt get in between the paper and the ruler, and it prevents the line from bleeding and the paper and ruler from staining. Takeda Brand: A drafting equipment manufacturer since 1935. As a manufacturer of design and drafting supplies, we offer products for technical universities, professional schools, and industrial high schools nationwide. It is widely used by those aiming for first-class and second class architects. Since its establishment in 1935, with the philosophy of contributing to technical and art education throughout the country, we have developed a variety of drafting equipment and drafting supplies, using the accumulated technology and know-how to develop art materials, school materials, model materials, medical education materials, and more.