The OttLite 20 watt replacement bulb 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 eyestrainDetails:Replacement bulb type MFor use only as a replacement bulb with specific OttLite lampsTrue colors, clear details and reduced eyestrainLow-heat, low-glare illuminationEnergy efficientRated to last up to 10,000 hours