L15830 15 W T8 Fluorescent Tube, 950 lm, 450mm, G13. Osram Lumilux T8 fluorescent tubes are energy efficient fluorescent lamps. They meet standard T8 sizing, which means they are tubular with a 26 mm diameter. These fluorescent tubes feature a G13 base. This series is available in a range of colours from 2700 K all the way through to 8000 K. Triphosphor tubes have longer life, a lower mercury content, better colour rendering and higher lumen maintenance than their Halophosphate counterparts. The tubes are available in a variety of colour temperatures from 3000K (warm white) to 6000K (daylight).