XS R3D Tritium Night Sights feature a traditional 3-dot tritium, notch and post sight picture. The rear is blacked out to increase contrast against the front sight. The front sight is available in orange or green and is equipped with our Ember Glow Dot Technology. Ember absorbs ambient light and glows in low light. The front tritium lamp charges the Ember dot making the front sight glow brighter than the rear, keeping focus down range. R3D sights are the brightest options for fast and accurate shooting in bright and low light.