Looks really good and fits perfectly - AIM Sports Inc AR15/M4 A2 Style Muzzle Brake

I bought it because I like the smaller diameter, but still maintaining the retro look. I saw a comment here saying that if you have a 556 then don't buy it because it is for a 30 cal, something along those lines. I don't know what he is talking about, because I have this flash hider on my AR and it does the job perfectly, it doesn't affect the accuracy or anything.

Now, the one that I got it has a greenish shine to it. The one on the picture looks matte black, so maybe mine was just a fluke? But I guess you can always spray paint it.