The Grainger 16W481 is a Philips 16-watt T8 fluorescent light bulb that provides 1600 lumens of light output. This 4 foot long bulb has a medium bi-pin base and a color temperature of 4100K. It has an average rated life of 20,000 hours and meets EISA standards for energy efficiency. This bulb can be used to replace less efficient T12 bulbs in existing T8 fixtures. It's ideal for commercial, industrial and residential lighting applications where a bright, energy efficient fluorescent bulb is needed.