Shotgun Barrel MD/Rail Mount Moss 500/590 Specifications Mossberg 500/590 Barrel and Magazine Tube Micro-Dot and Rail Mount, for mounting Optics and Accessories to your shotgun. The Mount and Rails are fully Customizable. The Mount can be configured into a Dozen different configurations to suite the Shooter's requirements. Dedicated Cantilevered Micro Dot mount is compatible with NcSTAR Micro-Dot Reflex Optics DDAB, DDABG, DDABL, DGAB, DXDAB, and DXGAB Includes Rail Adapter for the Micro-Dot Base for mounting Weaver/Picatinny type accessories/optics on top of the Cantilever mount. Includes two side Weaver/Picatinny type rails for attaching Accessories like Flashlight Lasers to your Shotgun. All Aluminum Construction. Black Anodized finish Length 2.7 Height 3.0 Weight 5.2 oz. NcStar Mossberg 500/590 Barrel Micro Dot Rail Mosberg 500/590 Barrel Micro Dot Rail