This receiver is manufactured with strict quality control, plus features an ejection port cover, forward assist, and an integral picatinny rail that extends the length of the handguard.There is a combat grade barrel at the heart of the m4-89, which is magnetic particle inspected and high pressure tested.Solgw includes their nox flash hider which is pinned and ready to mount a dead air sandman or nomad suppressor.Bolt carrier group & charging handle not included.Metal Finish: Black Hard Coat AnodizedAction: Semi-CompleteCaliber: 300 BlackoutBarrel Length: None, Optic ReadyCapacity: 13.90"Trigger: 4150 Chrome Moly Vanadium SteelSafety: 1:7"Oal: Combat GradeWeight: Black NitrideMuzzle: M-LOK Free-FloatReceiver Material: Black Hard Coat AnodizedBarrel Length Range: 13" to 13.99"