Chromalux light bulbs contain Neodymium, which filters away some of the yellow spectrum, creating a nicer, whiter light. The color is often described as a "pinkier white", vs. a "yellower white." This greatly improves contrast and increases readability. These bulbs are very long life. From 2500 to 3500 hours. That is 2 to 3 times longer than a long life bulb. A nice alternative to "full spectrum" compact fluorescent bulb which are more blue. These are labeled and marketed as ''full spectrum" however, we don't feel it is a legitimate use of the term, however we really like these bulbs and have sold them for over 10 years. "A" Style Bulbs $11.95 "R" Style Reflector Bulbs $22.95 Par Style Halogens $24.95 "R"Style with Halogen Filament $24.95