• Optum Ring system (O.R.S.) for the 35mm and 40mm Optum scope • This must be used in conjunction with an Optum scope • Makes it possible for shooters to change pin positions, fiber color, or fiber size by swapping between multiple rings in seconds • Features exterior fiber wrap that captures ambient light for a brighter pin • Adjustable fiber cover allows precise control over fiber brightness • Two 8-32 holes for installing a light in seconds • Eight pin positions • Threaded on the target side for optional sunshades and lenses • Only 40mm Optum sunshades will thread into the O.R.S. • Removable pin in keyway slot for perfect alignment every time Includes: • Optum ring body • Tubing and fiber cover - pre-installed • Pin and fiber (no fiber for no pin option) • Blue, red and green fiber included