First we created the original TFO day/night sight, then made it virtually indestructible with our hermetically-sealed TFX capsules. Next, we took TFX technology even further for professionals and shooters requiring maximum performance from their handguns - providing ultimate reliability, accuracy, and brightness no matter how tough things get. Features: Contrasting colored front sight ring for even faster focusQuick and accurate U-notch designAngled rear sight edge for emergency 1-hand operationAll features of our popular TFX handgun sightsUnmatched visibility in all shooting conditions 24/7Assembled in USA with quality swiss tritium for maximum brightnessGlows in the darkNo batteries requiredConcealed fiber cannot be seen by targetFortress finish provides a permanent protective coating for maximum protectionFits standard holstersEvaluated and recommended by National Tactical Officers' Association (NTOA) field testersPatentedFiber optic illuminationTritium illuminationHooked rear sight profile12 years limited warranty