Feyachi M40 3X Red Dot Magnifier with Flip to Left Side Mount Focus AdjustmentAbout this item This optics magnifier adds 3X variable magnification to your standard red dot sight and maintains an expansive field of view with comfortable 2. 4 inches eye relief. Fully multicoated clear glass for sharp sight picture, ensure good resolution, enhanced light gathering capabilities, and provide solid color fidelity. The quick release mount with included a lower 1 3 co witness spacer, with a fast flip to side engagement. The push button