I don't know if anybody is keeping track or not but I recently changed out the barrel on my RRA factory built 10.5" upper.

When I removed the FSB(straight pins) it IS parkerized under the front sight base. I don't know if this is the case on all their barrels or not, I only have a sample of one. I have one other RRA upper but I have no plans to change anything on it so I don't want to remove the FSB to look.

FYI