When you need to make a fast and accurate shot"" brightness counts. They brought fiber-optics to the shooting sports industry years ago for this very reason. They have now paired them with their tritium night sights to create a consistently bright sight picture-day or night! Their patented combination of Tritium and Fiber-optic technologies unites the best of both worlds. Whether you are in glaring daylight or complete darkness"" you can count on TFO(R) to provide a bright and reliable sight picture.