Fits Glock 17, 19, 22-24, 26, 27, 31-36, and 38 INCLUDING MOS pistols. XS night sights fit Glock Gen 1 to 5 pistols. Easy DIY Installation. Glows 24/7: Self-Illuminated tritium glows 24/7 providing a bright, battery free, low light visible sight picture. Fast Sight Acquisition: Highly visible 3-dot tritium sights provide fast sight acquisition and accurate shot placement day or night. Front sight equipped with an orange photoluminescent glow dot paired with tritium.