The Daniel Defense M4A1 features the M4A1 RIS II which has been in use by US Special Operations Command (SOCOM) for the SOPMOD II Weapons System since 2005. The M4A1 features a 14.5 Cold Hammer Forged M4 Profile barrel with a permanently attached Daniel Defense Flash Suppressor. This rifle also comes with the rugged and comfortable Daniel Defense Buttstock and Pistol Grip. The Daniel Defense California compliant design prevents the magazine release button from being engaged while fully assembled locking the magazine into the receiver. To release the magazine from the rifle the shooter will be required separate the upper from the lower by pulling on an extended (rear) takedown pin with an attached cord to make the process easier.