KUP is a bird cage designed for sparrows. Thanks to its modular structure, it allows the user to create various living spaces. The user clamps the units and hangs them on the tree with a polyester belt. In addition, it can be used individually without hanging and joining. The KUP units consist of PP sheets and are interconnected with tight-fit details. There is a passage on the front surface of the KUP. Near this entrance, there are 6 insert holes for wooden sticks.