Thank you for viewing this item. This is a fraction learning tool. I used it when I first started teaching fractions. It was left at my parents' house, and I also used it with my own children. I purchased it about 30 years ago, but it's made of wood and is sturdy, so it hasn't broken. Because of the angles, it was useful for math in general, not just fractions! I think it's recommended for beginners learning fractions because you can teach addition and subtraction of fractions by combining the blocks! It has been used by children and stored at home, so please understand that it is a used item before purchasing. Since it's made of wood, I'm afraid to wash it, so I will wipe it with alcohol before handing it over. Notes: ● Please note that there may be slight measurement errors depending on the measuring method. ● We cannot accept claims after purchase, so please make sure you understand before purchasing! ● It may be compressed when packing. ● Please forgive any wrinkles due to storage or packing. ● A non-professional is checking the item, so please understand that there may be oversight of stains, etc. Also, please refrain from purchasing if you are particularly sensitive to the condition, as it is stored at home. ● Please feel free to ask if you have any questions. ※ Please refrain from negotiating prices to avoid trouble.