This work is the result of TAKATOKU's participation in a 3-month residency project at HIAP - Helsinki International Artist Programme, during which he researched Finnish architecture, which is characterised by its use of natural light, and nature. He found birches have always been close to people in Finland, with their beautifully straight branches and finely floating leaves. The movement of these round, thin leaves creates an interesting flapping motion whenever the wind blows as if it were an installation created by nature power. Also during the research into the relationship between natural light and architecture, which is unique to Finland, he discovered composition and a sense of rhythm due to the low sun angle. Therefore, Instead of creating a similar moving mechanism, he came up with the idea of treating the movement of the leaves as a continuous film projection and cutting them out one by one. As a material for reconstructing it, he chose 'perforated steel banding', The various movements of the birches were expressed by using the existing holes as guidelines for the legal bending process.