The Rock River Arms LAR-15 A4 Carbine is RRA's standard flat-top carbine configuration, featuring a 16-inch chrome-moly barrel, carbine-length gas system, and RRA's factory two-stage National Match trigger. The A4 flat-top upper accepts optics directly without adapters. The two-stage trigger is standard across RRA's premium LAR-15 line, differentiating RRA from budget-tier manufacturers. Type: Rifle Action: Semi-Automatic Caliber: 5.56 NATO Capacity: 30 Year introduced: 2003, USA Weight: 6.25 oz Overall length: 32" Status: Active Intended use: Sport Shooting, Tactical