Rock River Arms DS1850: Rock River Arms is a leader in specialized Modern Sporting Rifles. The Rock River Rage Carbine builds on Rock River Arms' extruded flat top upper receiver. Made of 6061T aluminum, the receiver exhibits the clean lines and defined angles commonly associated with more expensive billet uppers while delivering comparable strength and precision dimensions. Its free-float handguard is constructed of 6061T aluminum and blends almost seamlessly with the upper to provide an elegant, unitized profile, balanced strength and rigidity across the optics platform. The carbine-length handguard also features a full-length MS1913 top rail and M-Lok rail configuration for easy accessory adaptation. Other key components of the Rage include a lightweight chrome moly barrel, A2 flash suppressor, carbine-length gas system with a low-profile gas block, single-stage trigger, A2 grip, and the RRA six-position tactical carbine buttstock. This model has a 16" barrel and a black finish.