DI Night Sight Set - for Springfield Armory XD, XD(M), & XD Mod.2Exceptional brightness in any light User replaceable fiber Field ready construction Building on decades of proven engineering and manufacturing excellence in tritium and fiber optic aiming solutions comes the Trijicon DI Night Sights. Designed for shooters who want daylight brightness and a constant aiming point, the dual illuminated Trijicon DI Night Sights are equipped with an industry first, interchangeable fiber. This patent pending design not