These smart nightlights have built-in photoelectric sensors to turn on automatically when it's dark and turn off when it's light. Works from dusk to dawn, or dark basements - anywhere where light is needed. Simply plug in to an outlet, and rotate in any direction to light the path - the wall, the floor - even the ceiling! LED bulb will last up to 100,000 hours - that's 34 years with 8 hours a night! Set of 2.