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. F48T8 44W/841 R17d High Output ALTO 1LP - 44 Watt - T8 Linear Fluorescent Tube - 800 Series - Wattage 44 Watt - Base Information: Green Base - Base: R17d [Recessed Double Contact Bay (RDC Bay-Fluorescent)] - Bulb Shape T8 - Bulb Type F48T8 - Color Temperature: 4100 Kelvin - Color Code: TL841 [CCT of 4100K] - CRI 86 - Length: 48 Inch. - Life Hours: 18000 - Lumens Initial: 4000 - Lumens Mean: 3600 - Mercury (Hg) Content: 3.5 mg - Picogram per Lumen Hour: 54 p/LuHr