The world of 0.2 m/sec or less of wind velocity. Our product, BS-02S is the only one available sensor for this measurement range.All users will be surprised at the clarified differences between calm state and 0.1 m/sec of wind velocity,also its? excellence of reproducibility.We provide such a special sensor with reasonable price.This one is used at a first-class maker?s research institute, and the research institute of the public institution the only one sensor for necessary recording of weak wind velocity data.