The Winchester SX3 was the predecessor to the SX4, featuring the original Active Valve gas system that first appeared in the Super X2. The 26-inch field configuration was the most common variant and established the Super X legacy of reliable cycling with mixed loads. Type: Shotgun Action: Semi-Automatic Caliber: 12 Gauge Capacity: 4 Year introduced: 2006, USA Weight: 6.7 oz Overall length: 46.5" Status: Discontinued Intended use: Field Hunting, Sport Shooting