This led bulb has a built-in sound sensor and turns on when 1) it's dark and 2) it detects sound. This is especially usefull in for example closets and basements. After 30 seconds it will turn off again.
Note: in daylight it will not turn on when it detects sound (energy saving).
Auto sound sensor (fast switching)
High sensitivity, high light and low power consumption
Suitable for corridors, pathways, stairs, gardens, yards, etc
Light Color: White (5500 - 6000K)
Connector type: E27
Detection range: ≤ 5M
Light: 720 lumens