This is a set of 5 Kumon educational material binders. ★With a set of 5, we can accommodate any combination of English, math, and Japanese. ★If you purchase without a comment, we will send you 5 math binders. You can store Kumon printouts in these binders. The thickness can be adjusted for 200 sheets or 400 sheets. When you start learning, it's difficult to keep all the printouts, but you don't want to throw them away... so you can file them by subject. Also, for children who have advanced to higher-level materials, their own completed materials become the best reference books. Filing them by subject is also great for remembering old grammar when they get stuck. They fit exactly 200 or 400 sheets, without creating wasted space. They are easy to put on a bookshelf. 《Material》Paper Please take a look here ↓ #Kumon related, children's enjoyable collection If you have any questions, please feel free to comment.