This deluxe set includes nine overhead circles divided into 1/2, 1/3, 1/4, 1/5, 1/6, 1/8, 1/10, 1/12, and 1, with storage box/work tray. Color coded with all products. Teaching notes included. Set of 51. Grade 1 and up. Each of the five rings in the set is divided into equal intervals and contains a well-marked scale.