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 only allows the ability to replace the fiber in the field, it allows the user to choose among several fiber and ring retainer colors to configure a personalized aiming solution.Trijicon DI Night Sights feature a chemical and heat resistant fiber, finished with the same proprietary technique as the Trijicon ACOG, coupled with a tritium lamp capped with a sapphire jewel. This dual-illumination technology amplifies collected light, ensuring an ultra-bright aiming point in any light from daylight-bright to low-light to complete darkness. Trijicon DI Night Sights offer shooters the unique features needed for an any-light pistol aiming solution, with the durability and reliability Trijicon is known for. Professional installation recommended. Front Sight Width: 0.160″. Front Sight Height: 0.264″. Rear Sight Height: 0.309″.