You can conserve electricity and provide a lighted, safe environment at night by using the battery operated Motion-Sensor LED Stair Light. The module has a built in photocell that is only activated by darkness. Once activated, the module will remain in a stand-by, low-glow mode. While in in low-glow mode, the motion sensor will detect movement and the LED will brightly light up the area around it. As the sun rises or the location becomes lit, the module will shut off, extending the life of your batteries. For your convenience you can set the automatic shut-off time between 20 seconds or 1 minute. It can be mounted virtually anywhere you may need light; your home's stairway, bathroom, hallway or kitchen. This product is weatherproof, so it is versatile enough to be mounted outside your home on the front porch, back patio or shed. The Motion-Sensor LED Stair Light requires the use of three C batteries for power, sold separately.