Source.

I thought this picture was kind of an interesting setup. The M27s have been issued with accompanying VCOGs, so the ACOG stood out a bit. This looks like one of the 3.5x TA11MGOs that was bought for the M249s. Which I suppose makes sense, if the unit supplying the M27 has shelved their M249s, they probably donated the optic to the rifle. Although I do wonder what happened to the original VCOG. If this was a replacement of necessity, or if someone who was able to make it happen prefered the ACOG & RMR bundle over the LPVO VCOG.