The Sparco 12 Standard Metric Ruler offers accurate raised sharply defined Imperial ruling with 1/16 markings and metric calibrations. It is made of rigid strong plastic material that is lightweight and durable. The design of this 12 ruler features a pencil groove. It also includes holes in the center for storing in your two-ring or three-ring binder. Take this tool to school for your studies or use it at home for a variety of needs including drafting and crafts. It is suitable for all ages.