Space-saving foldable binder box for the school backpack: School notebooks have to endure a lot in everyday school life. They are packed into bags multiple times a day, sometimes more gently than others, may get bent in an almost empty backpack, and can encounter a forgotten banana or a leaking bottle. Often, they look worn shortly after the school year begins. You can equip your child's school backpack with the binder box, so the expensive, once carefully covered notebooks remain usable for longer. This way, school notebooks, as well as presentation folders, writing pads, and softcover books in A4 format, have their own secure place. The compartments can even be divided into several colored sections, making it immediately clear where to look for a specific notebook. An extra compartment for a ruler keeps the 30 cm ruler safe from breaking. Keeping things organized in the backpack couldn't be easier! The binder collector is attached using clips to the book compartment of coocazoo backpacks. A new compartment can thus be added in no time, which can be expanded or contracted depending on the contents, similar to an accordion. Unlike traditional binder boxes and closed folder cases that have a fixed size, the foldable binder box from coocazoo saves space.