Can anyone tell me why I see some Noveske N4 lowers marked .556 and some have no marking? I am mainly referring to some of the stripped lowers I see posted for sale. Also, might as well ask the question. What's the general opinion on their lowers? Don't know that I have really ever seen anything written about those. I know everyone talks about their uppers. Guess lowers just aren't as sexy as uppers?

