This is the Otohime device in the ladies' toilet in a Toto showroom (which I entered with permission of the showroom staff). The dark field with the hand pictogram is a motion sensor, and when a hand is waved in front of the sensor, a loud flushing sound is heard for 25 seconds to cover any potential sounds of the toilet user. The device stops 25 seconds after the last activation or if the Stop button underneath is pressed.
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