Complete upper receivers include: AR-10® port door assembly (EA1165), AR-10(T) port door rod (EA1170), AR-10/M-15 port door spring (EA1167), and AR-10 forward assist kit (10005001KIT).
AR-10(T) complete upper – comes with longer port door rod than standard for customers wanting to free float their rifle – the longer port door rod is needed so it doesn’t slide out of the port door.
Caliber: 7.62X51 mm / .308
Upper Receiver: Forged, flat-top with MIL-STD 1913 rail, 7075-T6 aluminum
Finish: Anodized aluminum upper, manganese phosphated steel barrel