The armasight co-lr (clip on long range) is a night vision unit that mounts in front of an existing day scope and converts the day scope to a night vision scope, effective up to ranges of 1000 yards.The co-lr can be mounted to or removed from a standard picatinny rail in seconds, with no tools required.The co-lr is recommended for use with day scopes of up to 10x magnification.Because the co-lr is mounted in front of your day scope, the shooters eye relief is not altered and shot release and follow through all remain intuitive.As the unit is factory bore-sighted to better than 1moa accuracy, no alteration in zero is experienced, so it truly is as simple as mount-focus-shoot, as familiar as shooting in the daytime.Lens system is f1.54, f108mm.Resolution: 64-72 Ip/mmMagnification: 1xObjective: 108mmField Of View: 9 DegreesGeneration: 3Battery: CR123A/AADimensions: 11.70" x 3.80" x 2.80"Weight: 2.40 lbsFocus Range: 15mm to InfinityInfrared Illuminator: YesBattery Life: Up to 45 hrs