Pretty. First I have heard of it, but neat and very cool you went to the proper effort to get the right length, right device, and SBR'd it instead of gheying it up with a brace. Should also cause a few collector heads to lightly explode. It's a real XM177E2 because Colt says so. That's the model number in the catalog and on the side
Also cool it has the third position marked properly, since I have rarely seen that. Seems most inspectors get upset if a semi maker does that. Got a silly mark on one of my group buy lowers, because we couldn't get AUTO even after asking.
Too bad forward assist (and fences??? Is that proper?), but what can you do?