Math Teacher Aids: Large size ruler for geometry drawing and math lessons, suitable for classroom, school or office. Large Numbers: Math geometry ruler has clear large numbers on it, easy for you to measure and read, suitable for chalkboards, whiteboards, erase boards and more. Easy to Use: Teaching ruler is lightweight and easy to hold, ideal drawing aid for teachers. Material: Drawing math geometry tool is made of durable material, strong and durable, wear resistant, not easy to deform, won't scratch your hand. Widely Used: Math geometry teaching supplies are essential tools for architects, engineers, artists, designers, teachers and more. Size Chart:59.5cmx51cmx58.5cm/23.43inchx20.08inchx23.03inch Package Includes: 1Math Geometry Ruler Note: Please allow slightly errors due to manual measurement and different monitors.