New Mid-length 16" Armalite barrel with M4 cuts, .750 at the gas block. This is a newer barrel, Armalite didn't used to stamp their barrels, but they started to in May of 2012 as an Armalite rep confirmed Here
The stuff on the barrel in the pics is Oil. It's been stored in an anti rust plastic bag.
$110 shipped USPS MO, PP gift or PP +3%
Would trade towards an SSA or SSA-E (prefered)