Motion Sensor Bulb

This bulb automatically turns on when you enter the room. It's called a motion sensor bulb. The passive infrared sensor inside it detects changes in heat and movement within its range, which triggers the bulb to switch on. If there's no activity for a while, which triggers the bulb to switch on. If there's no activity for a while, the built-in timer deactivates the bulb and it turns off automatically.