The Chromalux bulb has its origin in Finland land of the Midnight Sun where life is spent in almost total darkness for a few months each year. Extensive research and testing there resulted in the design of this unique light source which closely simulates natural sunlight. Chromalux Full Spectrum bulbs mimic natural daylight. They improve reading conditions reduce eye strain reveal natural colors and textures and help to promote a feeling of well being. Average life per bulb is 5000 hours.