The Trijicon HD Night Sights MOS fit rear Orange front for Glock Models 17-39 deliver rapid target acquisition in transitional lighting with a three-dot green tritium night sight set, where the front sight features a taller blade and a photoluminescent ring for fast recognition, while the rear sight is outlined in black with a wider U-shaped notch to improve visibility and alignment. Designed for tactical shooters, these sights combine durable matte finishes and precision engineering to provide reliable performance under demanding conditions, and the MOS compatibility ensures a secure fit for Glock models including 17MOS, 19MOS, 34MOS, 45MOS, and traditional 17, 19, 22, 23, 24, 25, 26, 27, 28, 31, 32, 33, 34, 35, 37, 38, 39 and 45 variants. The front surface of the rear sight is steeply hooked to aid in emergency one-handed slide operation, and the green tritium lamps are warranted for 12 years from date of manufacture for long-term illumination. Note that professional installation is recommended and the HD MOS Fit sights are not designed to be used with a red dot optic, as they are not tall enough to be viewed through a red dot window.