Fulham's FLPL50-S-B FreeLite photo-luminescent exit sign is self-luminous and uses no electricity. It has an aluminum background and field applied directional chevrons. With a 20-year estimated life and virtually no maintenance (no bulbs or battery to replace), you can feel confident that this glow-in-the-dark exit sign will provide high visibility in total darkness and smoke filled conditions for years to come. This exit sign is designed for surface mounting only. Flag or ceiling mounting is possible, but optional frame and mounting bracket (sold separately) are required. It has a legible viewing distance of 50 feet.