Thank you for viewing. SUN Hemmi's Bamboo Slide Rule This is a bamboo slide rule (calculating ruler) made by SUN (Hemmi Keisanki Kogyo). One has a box. Model number unknown. One does not have a box. Model No. 250. These were used as science teaching materials and engineering calculation tools, and are now popular for collections and display. • Material: Bamboo • Accessories: Original box included (box has some damage) • Condition: Some rust is present. Please consider purchasing if you understand that these are used items and have been stored for a long time.