Brightness Settings: Choose between 10 levels of brightness in manual mode or switch to auto mode. Unlimited Eye Relief: Non-critical eye relief for rapid target acquisition Parallax Free: All red dot and holographic sights will exhibit some small amount of parallax. Matching current industry practice, this small amount would be considered "parallax free" and will make a negligible difference in performance. 6 MOA Dot: The daylight bright red dot is easy to see and paints targets regardless of lighting conditions or background.