The OttLite 13 watt replacement tube delivers the right mix of brightness and contrast to bring true colors and comfortable clarity to your world so you can enjoy your time even more. You’ll see colors accurately and fine print and details with ease under this unique low heat, low glare illumination that helps reduce eyestrain. Please note this version has an electronic ballast and will work with OttLite 13w lamps purchased after 2008. Details: Replacement bulb type E For use only as a replacement bulb with specific OttLite lamps with a electronic ballast True colors, clear details and reduced eyestrain Low-heat, low-glare illumination Energy efficient Rated to last up to 10,000 hours