The Trijicon ACOG 4x32mm Tritium/Fiber Optic is an internally-adjustable, compact telescopic sight with a tritium illuminated reticle pattern for use in low light or at night. It combines traditional, precise distance marksmanship with close-in aiming speed. This model’s design is for use with the M16 family, every feature of its mechanical and optical design was chosen for a single purpose: to provide increased hit potential in all lighting conditions.
There are no batteries to worry about losing or having fail during a vital moment, this optic’s reticle is lit by a tritium lamp coupled to a fiber optic light pipe. During the day, it’s powered by the sun itself, and during the night, it’s lit by tritium and what natural light is collected by the fiber optic. Reticle brightness is automatically adjusted, there is no need for buttons or a dial that could fail.
The ACOG 4x32mm Tritium/Fiber Optic is legendary for a reason, so don’t hesitate to trust one.
Please double check that this is the reticle pattern you want, as Trijicon makes a number of reticles for their ACOG line of sights.