Highly visible, tritium dot front sight surrounded by a large white ring epoxies over the existing front bead sight to help improve target focus and low light sight acquisition and sight recovery after muzzle flash. Installs over front sight beads from .125' - .140' diameter by filling the cavity on the underside of the sight with Brownells Acraglas Gel, then pressing the sight over the bead and allowing it to fully cure. If existing bead is too small or too large, replace with Brownells #6 bead for 3-56 threads or #26 for 6-48 threads. Some shotgun barrels may require drilling and tapping of existing hole to 6-48 for installation of #26 Brownells bead. Remington Pedestal model with stepped bottom fits Remington shotgun barrels with front sight pedestal. Vent Rib model with flat bottom fits shotgun barrels with ventilated ribs. Plain Barrel model with cupped bottom fits round shotgun barrels. Includes instructions. SPECS: Machined steel, black, matte finish. Big Dot .161” (4mm) diameter. Fits beads from .125” (3.2mm) to .140” (3.5mm). Remington Pedestal fits Remington front sight pedestals. Vent Rib fits ventilated ribs. Plain Barrel fits round barrels. Includes instructions.