*The magnifying glass and red dot are designed to increase your effective shooting range*Red dot sight allows for accurate, wide-open shooting on both eyes.*Reflective Scope with Picatinny Rail Mount and Side Flip-Mount Focus Adjustment Magnifier, Absolute Co-Witness with A2 Front Sight.Magnifier and red dot are designed for increase your effective shooting range. This optics magnifier adds 1.5X - 5X variable magnification to your standard red dot sight and maintains an expansive field of view with a comfortable 2.2-3.6 inches eye relief.