Never worry about turning your tail light on or off again! The Reflex Auto tail light has both optic and motion sensors to determine when to automatically activate the light. When darkness and motion are detected the light turns on instantly! The combination of active and passive safety help provide even more visibility. The active safety refers to our standard tail light technology, perfected over years of development. The passive safety component refers to our outstanding CPSC reflector design that has exceeded highest governmental standards for many years. The 5 super bright modes, over 180 degrees of visibility, and various mount options will help you stand out from the crowd and guarantee you'll be noticed at night!