The M2124 is a rugged, clip-on night vision device (CNVD) based on military nomenclature AN/PVS-24 used by U.S. Special Operations Forces. The advanced design of the Model 2124 eliminates the typical requirement of removing a primary/day sighting system, since it mounts in line with a standard day optical sight.Combining day and night vision sights reduces the need to re-zero, since the primary sight remains undisturbed. Using the M2124 with a primary sighting system also maintains a user's consistent eye relief and shooting position and retains the user's muscle memory.The M2124 easily attaches to a MIL-STD-1913 rail interface system by operating the provided locking, quick-disconnect, single-throw lever-mounting system. The unit may also be used as a handheld observation device.With an 8-degree field-of-view, the M2124LR (Long Range) is optimized for 4x-20x magnified riflescopes. Mounted in front of the scope, the M2124LR allows the shooter to maintain consistent eye relief and shooting position.