The HD Night Sights were specifically created to address the needs of tactical shooters. They are a self-luminous, three-dot night sight set that features a highly visible photoluminescent paint outline to quicken sight acquisition, along with a "U" notch rear sight that's angled and serrated to reduce glare and aid in front-sight focus. The Tritium gas lamps are contained within protective aluminum cylinders and have additional silicone rubber cushioning. Each Trijicon tritium lamp is capped with a sapphire jewel that helps evenly distribute the light and also acts as an additional layer of protection from puncture and cleaning solvents.