Trijicon acog - Trijicon ACOG 3.5x35 Scope, Dual Illuminated Crosshair .223 Ballistic Reticle w/ TA51 Mount, Red TA11J, Amber TA11J-A, Green TA11J-G

I was introduced to the ACOG series during my first deployment to Afghanistan and I have relied on them as a primary optic ever since. Extremely sturdy and reliable with a side benefit of never having to worry about a battery going out at the wrong moment, (Murphy's law: a system will fail at the moment you need it the most.) I use this particular ACOG with BUIS and a 45 degree offset red dot for work under 25m. You will not regret this optic.