XS Sights Big Dot Tritium Front Shotgun Sight combines tritium with a patent pending glow dot for superior front sight visibility in all lighting conditions. The optic orange is engineered to provide a high-contrast sight picture in bright light while maintaining visibility in low light. This sight requires a .125" - .140" diameter bead for installation and comes with a replacement bead suitable for Mossberg shotguns. If the current shotgun bead does not fit this diameter or is not a Mossberg, a Brownells #6 or #26 front bead must be purchased separately.Key FeaturesColor: Features a green tritium dot with an orange outline for enhanced contrast.Included Bead: Kit includes a replacement bead specifically for Mossberg shotguns.Installation: Installs using any two-part epoxy, such as JB Weld.