The Mossberg 940 Pro Tactical SPX is a defensive 12 gauge semi-automatic shotgun built as an upgraded SPX variant of the 940 Pro Tactical platform. It features an 18.5" barrel, 3-inch chamber, 7+1 capacity, gas-operated action, optic-ready receiver with RMSc footprint, included adapter plates for RMR, Docter & Leupold footprints, metal ghost ring sights with protective wings, fiber optic front sight, enlarged controls, adjustable stock & an M-LOK forend with integrated heat shield. Designed for home defense, tactical training, professional use & high-volume range work, the SPX adds enhanced accessory mounting, faster sighting options & more practical control surfaces than the standard 940 Pro Tactical. Mossberg has a long-standing reputation for rugged defensive shotguns & the 940 Pro Tactical SPX continues that reputation with a self-cleaning gas system, corrosion-resistant internal components, oversized controls and durable synthetic furniture. The platform is recognized for reliable cycling, soft recoil compared with pump-action tactical shotguns, fast follow-up capability & excellent optic integration for defensive use. Its Accu-Choke-compatible barrel, installed cylinder bore choke, adjustable length-of-pull stock, QD sling cups & M-LOK slots give the shotgun strong flexibility for modern tactical setups. Overall, the 940 Pro Tactical SPX is a well-equipped semi-auto defensive shotgun with strong reliability, practical ergonomics & high out-of-box capability.