The Aero Precision M4E1 Enhanced in .308 Winchester with 18-inch barrel is the premium configuration of Aero's large-frame lineup. Geissele SSA-E trigger, BCM Gunfighter charging handle, and ATLAS R-ONE handguard are standard. The 18-inch stainless barrel and M5 receiver set make this one of the most capable factory .308 ARs under $1,500. Type: Rifle Action: Semi-Automatic Caliber: 308 Winchester Capacity: 20 Year introduced: 2019, USA Weight: 118 oz Overall length: 38.5" Status: Active Intended use: Hunting, Precision Rifle, Long-Range Shooting