ONE HORSE 5.56 NATO COMPLETE UPPER RECEIVER W/MEDIUM PISTOL BBL FOR AR-15 Build a compact and highly maneuverable AR platform with this 5.56 NATO complete upper receiver, engineered for reliability, fast handling, and consistent performance in tight spaces. Fully assembled and ready to install, this upper is ideal for AR pistol or SBR configurations. At the core is a 5.56 NATO barrel paired with a pistol-length gas system, delivering reliable cycling in a compact format. This setup is optimized for shorter builds where responsiveness and maneuverability matter most. The 7" M-LOK free-float handguard enhances barrel stability for improved a Mfg: One Horse