I don't remember but if BeltFed is in North Carolina he threaded my plain barrel a year or so ago. I sent the entire upper. Excellent craftsmenship and I think the turnaround was no more than a day or two.

An old M16A1 flash suppressor screwed right on. M16A2 compensator (on M16A2) -- no bottom slots -- on top, M16A1 flash suppressor (on M&P15-22) on the bottom.



-- Chuck