All 940 Pro Waterfowl shotguns now come optic-ready with patent-pending receiver cuts that accept direct mounting of Shield RMSc-pattern micro dot sights for improved eye alignment and target aquisition.Inside you will find a host of corrosion-resistant internal parts — including a boron-nitride coated gas piston magazine tube and hammer and sear — for improved performance in the blind in the pit or while traversing upland fields. For additional protection our 940 Pro Waterfowl models feature a coated return spring tube chrome-lined chambers and bores and a stainless steel return spring to help when facing wet unforgiving conditions.