Broadband Multi-coated Lens to Provide Crystal Clear 3X Image. Wide Field of View - 30 Percent Bigger Than Comparable Models from Other Brands. Windage/Elevation Adjustability for Optimum View Centering. Innovative Flip-to-Side Mechanism for Quick Transition between 1X and 3X Image. Adjustable Eyepiece for Easy Dioptric Correction. Precision Machining and Anodizing for Maximum Strength and Wear Resistance. Patented Quick-detach Lever Lock Mounting Base. 42mm Center Height for Most Common Dot Sight Combination. Completely Sealed and Nitrogen Filled for Fog/Weather Proof