Sturdy Numarkas! This "see, touch, and understand" educational material is perfect for Montessori and STEAM learning to eliminate stumbling blocks in arithmetic. My children (2 and 4 years old) actually use this! ■ Features of this product ・Sturdy resin case ・The box size is the golden ratio. Engraving of the golden ratio on the back (photo 5) ・Slide-type lid that clicks into place ・By sliding the lid halfway, you can hide how many balls are on one side ・You can roll the balls with the lid closed ■ Contents ・Numarkas body [Brown] ・10 balls [Blue marbles] + Add 10 more balls 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 private sale. We offer discounts for multiple purchases and repeat customers, so please comment. Popular keywords... Shichida method Type... Numbers