Tritium Pro night sights transition from standard white dot sights during the daylight, to glowing green dots in the dark. Tritium does not need batteries and does not need to be charged with light. Front sight FOCUSLOCK ring for even faster focus. Fits most standard holsters. Fits- 1911 MODELS .270 Front/.500 Rear Novak LoMount* cut (1911 3 Officer & 4.25 9mm/.40 S&W)