Action. Motion. Lights. Instant light activated by motion. Light turns on automatically when motion is detected from up to 19 ft. away. Once the source of motion is cleared, it will take 10 minutes until the bulbs turn off. Great for outdoor use as a preventative measure against trespassers or indoor as a handy hands-free way to light up a space as you walk by. The motion light bulbs work off of microwave technology, which can sense movement through solid objects like doors, windows, floors, the cover of an enclosed fixture, or any solid objects. This motion sensor on the bulbs are sensitive and it will see you before you see the bulb.