Innovative tunnel sight with highly visible red or green rod provides exceptional sight contrast in all light conditions. Front sight dot is only visible when using correct head alignment, forcing proper shooting form and increasing accuracy. Red or green fiber optic rods are easily interchanged allowing you to change sight color when light conditions change. Designed to fit ventilated ribs with removable front beads. Magni-Comp contains a compact, stainless steel base that is secured firmly to the ventilated rib using included screw, making it ideal for heavy recoil loads or ported barrels. Sight base uses a locking spring to keep the light rod secure, yet allows easy interchangability Mfg: Hiviz SPECS: Magni-Comp – Base – 1704 stainless steel, matte black finish, 1 1/4" (3.1cm) long. Rods polymer, (1) red, (1) green, 11/16" (17.8mm) long x .07" (1.8mm) dia. Includes five screw sizes: 3-56" fits Winchester, Beretta, Benelli, and Ruger shotguns