The Mepro MMX3 micro magnifiers are compact, lightweight magnifiers that will extend your effective range of your red dot or 1x reflex sight. Weighing in at 6.1 oz. respectively they reduce the footprint, saving rail space and weight on your firearm. Elevation and windage dials provide precise FOV line of sight alignment. A wide FOV enables rapid target acquisition with both eyes open which is ideal where agility, and speed are of theutmost importance.The Mepro MMX3 micro magnifiers attach to any MIL-STD-1913 rail directly behind your optic. When not in use the Mepro MMX3 can be "flipped" out ofthe way by depressing a pushbutton. SPECS Magnification: 3x Mfg: Meprolight