Sunlite 30 Watt T12 Colored Straight Tube, Medium Bi-Pin Base, NaturalFluorescent 30 watt natural T12 colored straight tube features a medium bi pin base, provides a light output of 1500 lumens at a color rendering index (CRI) of 86 and can last an average of, 18,000 hours. A warm, pleasant light, cooler than Warm White, but warmer than Cool White, while having much higher color rendering than either, Natural complements skin tones and is often used in restaurants, lobby"s and cafeterias.