The sons of liberty gun works m4-89 was designed to be ultimate fighting rifle.It features their m89 drive lock handguard, liberty fighting trigger and the vltor a5 buffer system.Solgw has nothing to hide with their quality builds.This rifle has a 16" barrel and an a2 flash hider.Action: Semi-AutoCaliber: 5.56x45mm NATOBarrel Length: 16"Capacity: 30+1Trigger: SOLGW Liberty Fighting TriggerSafety: AmbidextrousStock Description: Adjustable B5 BravoMuzzle: A2 Flash HiderReceiver Material: 7075-T6 AluminumSights: None, Optic ReadyTwist: 1:7"Barrel Length Range: 16" to 16.99"Stock Finish Group: Black