Sons of Liberty Gun Works believes in Quality Mil-Spec or better parts. They believe there is no substitute for quality and that your gun should be built right the first time” ready for hard use right out of the box. They believe a quality” accurate and long lasting barrel is the heart of a Combat Grade weapon. They believe in properly tuned weapons using the correct gas system length and quality buffer system components. All of these beliefs are forged together to bring you the SOLGW M4-89 Complete Upper with 13.7″ 5.56 NATO Combat Barrel and a NOX Muzzle Device. Featuring the M89 Handguard. They believe in their products and back them up with a Lifetime Warranty. Does not include a BCG or Charging Handle.