Environmentally Responsible Lamps Sustainable Lighting Solution with ALTO Lamp Technology - low mercury and energy efficient.;95% Lumen Maintenance.;24 month warranty period. Philips leads the industry with the lowest level mercury technology. Reducing the mercury level (source reduction) during the manufacturing phase is essential to creating products that are less harmful to the environment. Full Line of 6" Leg Spacing.;Outstanding Lumen Performance.;HI-VISION Phosphor.;Reduces the impact on the environment.;Low mercury.;Energy efficient.;Available in 32 watts with 3000,3500, 4100, and 5000 color Temperatures. Ideal for commercial applications with 2' x 2' fixtures.