Sturdy Numarkasten! This "see, touch, and understand" educational material is perfect for Montessori and STEAM learning to eliminate stumbling blocks in math. My children (2 and 4 years old) actually use this! ■ Features of this product ・Sturdy resin case ・The golden ratio is engraved on the back of the box ・The size of the box itself is also the golden ratio. ・You can roll the balls with the lid on ・Transparent lid (new) ■ Contents ・Numarkas body [Silver] ・10 balls [Blue marbles] +10 balls will be added for 200 yen. If you purchase them separately, it will be 400 yen. Please comment before purchasing. Size (approx.) Width 15, Length 10, Height 3cm ■ Target age 3 years old and up Numarkas Early childhood education Educational toys Nature Science Please refrain from purchasing if you are concerned about the details, as this is a amateur sale. We offer discounts for multiple purchases and repeat customers, so please comment. Popular keywords... Shichida method Type... Numbers