When you open the window, the blade will fall off and a pippo sound will notify you that the window is open. (approx. 75 db) ● If you switch on the main unit to the "stop" and then remove it, you can open and close without making any noise.
●ドアや窓が開くと警報音を発して侵入者を警告する
●アルミサッシ用