Aero Precision M4E1 pistol with 11.5-inch barrel and SBA3 pistol brace. Compact configuration in enhanced M4E1 receiver set. Type: Semi-Auto Rifle Action: Semi-Automatic Caliber: 5.56x45mm Capacity: 30 Year introduced: 2018, USA Weight: 58 oz Status: Active Intended use: PDW/Home Defense