XS Sights XS Ember Big Dot offers superior front sight visibility in all lighting conditions. Upgrade a home-defense shotgun to a high-contrast front sight that absorbs light and glows in less than ideal conditions. Optic Orange is designed to offer a high-contrast sight picture when shooting in bright light conditions and maintain its visibility in decreasing light levels. To ensure visibility in low light when uncharged, optic orange is primarily based on yellow with a hint of red. The increased surface area of the convex dot increases light absorption, intensifying the charge of the glow properties of the dot. Fits on shotguns where 0.120"-0.140" diameter bead sits directly on barrel. Kit comes with replacement bead for Mossberg shotguns. Installs with any two-part epoxy, like JB Weld. SG-2005-2N