Mossberg 940 Pro SPX Thunder Ranch, Semi-automatic Shotgun, 12 Gauge, 3 Chamber, 18.5 Barrel, Optic Ready, Heat Shield, 7 Rounds 85181 The 940 Pro Thunder Ranch comes optic-ready, with patent-pending receiver cuts that accept low-profile direct mounting of Shield RMSc-pattern micro dot sights for improved eye alignment and target acquisition. Chock full of additional features, this shotgun - with design input provided by Thunder Ranch President and Director Clint Smith, is equally well-suited for a day at the range or put to use for home security needs.