The ACOGs combine traditional, precise distance marksmanship with close-in aiming speed. Although the ACOGs have many features which are very advantageous for military use, they were developed by Trijicon without government funding.

Designed 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 -- without failure-prone batteries.

The TA31ECOS Brown color. It has a Dual Illumination Red Crosshair .223 Ballistic Reticle.  It comes with a mounted brown 
DocterŽ Sight, Backup Iron Sights, an A.R.M.S. Throw-lever mount and a Dust Cover.