UTG 1PC Offset Picatinny Mount Precision Machined from Aircraft-grade Aluminum Alloy with Anodized Black Matte Finish Friendly Hex Screws with Retention Features and Full Length Locking Plate to Guarantee Easy Installation and Secure Fit Fits All Picatinny/Weaver Rails 43mm Bi-directional Offset Provides Extended and Comfortable Eye Relief Ring Distance from Outer Edge to Outer Edge 85mm