XD HR Night Sights for Sig Sauer handguns are designed to maximize target acquisition and functionality, even in long-range engagements. The thinner front post keeps the sight picture open, improving field of view and situational awareness. The XD HR Night Sights use a silicone rubber cushion to further protect the tritium-phosphor lamps. Protective aluminum cylinders for the tritium lamps U-notch rear sight design Sapphire jewel window on lamps for protection and to evenly distribute light 9mm, 357 Sig do NOT fit P938 or P365 These XD HR Night Sights are compatible with Sig Sauer handguns (not for Sig 1911 pistols). Mfg: Trijicon