Aero Precision M4E1 complete rifle with 16-inch mid-length barrel, ATLAS R-ONE handguard, and enhanced receiver set. Mid-priced precision build. Type: Semi-Auto Rifle Action: Semi-Automatic Caliber: 5.56x45mm Capacity: 30 Year introduced: 2016, USA Weight: 62 oz Overall length: 32.5" Status: Active Intended use: General Purpose/Patrol