The Philips 37900-8 FB32T8/TL835/6/ALTO 32-watt T8 u-bend fluorescent tube Lamps are incredibly powerful, environmentally responsible, long life lamps with an ultra-slim profile. This translates into reduced maintenance and disposal costs and also allows the use of smaller fixtures, which reduces ceiling clutter. It has a warm color temperature of 3500K and an average life of 20,000 hours. Better for the environment, same performance characteristics: Lamps with ALTO II technology have 50% less mercury than prior ALTO T8 lamps, making these lamps the most sustainable linear fluorescents available. Best of all, these lamps offer the same performance levels as ALTO lamps (life, energy, and light output).