The Sons of Liberty M4-L89 URG 16" 5.56 NATO Upper Receiver is designed for performance and reliability, making it an ideal choice for your next AR-15 build. This complete upper receiver features a robust construction with a 16-inch 5.56 NATO barrel, ensuring accuracy and durability for various applications, including home defense and competitive shooting. The proprietary L89 handguard offers enhanced ergonomics and versatility with M-LOK slots for mounting accessories. Engineered for performance, this upper includes an A2 flash hider and an innovative Drivelock barrel nut system for secure attachment. Upgrade your firearm with this expertly crafted upper receiver group from Sons of Liberty Gun Works.