Trijicon 4x32 TA31 RCO M4, Red Chevron $899 New!!! -Trijicon 4x32 BAC, TA31 RCO M4 CP, Red Chevron BDC Reticle for the .556 NATO up to 800yds. This Acog has the Better 3 Clicks per MOA Elevation & Windage adjustments for a more precise Zeroing that equals more precise Bullet Drop Compensation...