Primary Arms 3X Red Dot Magnifier (GEN III) with Quick Detachable Flip To Side Mount (Standard Height) Primary Arms new 3X weapons grade magnifier. Features internal azimuth and elevation adjustments to center the dot. Field of View: 39.37ft at 100 yards. Standard Hight, Perfect for all medium lower 1/3 cowitness red dots. Puts center of magnifier 1.64-Inches above the top of mounting rail.