Outstanding performance and reliability When you select Philips TuffGuard Fluorescent lamp with ALTO lamp technology, you are reducing the impact on the environment, while the coating helps to protect your customers, employees, and reputation. Philips TuffGuard fluorescent lamps meet sustainability requirements because they reduce the impact on the environment with low mercury, energy efficiency and long life.The patented green endcaps mean you're using ALTO low-mercury technology. The 16 mils thick coating on TuffGuard fluorescent lamps forms a protective seal from end to end and is guaranteed to last the average rated life of the lamp under specific conditions Sustainable Lighting Solution - Philips TuffGuard lamps reduce the impact on the environment with low mercury.;Energy Efficient for a greener, brighter future;Long Life to assist with lowering your maintenance costs and reducing waste.