The Sons of Liberty M4-EXO3 Series are built with duty and service at their core. These firearms are available as a pistol with an 11.5" barrel, a rifle with 13.7" barrel, and a rifle with a 16" barrel. All M4-EXO3 are outfitted with a 4150CoMOV barrel with a 1:7" twist. The M4-EXO3 series also features a proprietary Liberty Fighting Trigger and an ambidextrous Liberty Charging Handle. Other features include a full length handguard with lightening cuts for greater rigidity and reduced weight. Features of the M4-EXO3 Series: Available as a pistol with an 11.5" barrel, a rifle with 13.7" barrel, and a rifle with a 16" barrel 4150CoMOV barrel w/ 1:7" twist Liberty Fighting Trigger Liberty Charging Handle (ambidextrous) Sons of Liberty Gun Works SOLGW M4-EXO3 5.56mm 11.5" Pistol M4-EXO3-PISTOL-11.5