The all-new 990 Aftershock SPX is a 12-gauge, 3-inch semi-auto tactical firearm that enhances the compact Aftershock platform with advanced SPX-level features. Small in size yet big on performance, the 990 Aftershock SPX combines proven Mossberg reliability with modern accessory compatibility and an optic-ready design. This highly maneuverable platform is available with 14.75-inch or 18.5-inch barrel options.
990 Aftershock Gas-Driven Reliability
At the core of the 990 Aftershock SPX is a durable gas-operating system fully contained within the forend, engineered for consistent, reliable cycling. Critical internal components—including the gas piston, magazine tube, hammer, and sear—feature nickel-boron coatings and specialized finishes for enhanced corrosion resistance and smooth operation. Performance features include an enlarged and beveled loading port, elongated pinch-free elevator, and a high-visibility anodized orange follower. The oversized, ergonomic top-mounted safety is easily operated by both left- and right-handed shooters and includes a clearly visible red indicator.
SPX DNA: Built to Run
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Enhancing versatility, the 990 Aftershock SPX incorporates the SPX handguard shared with the 940 Pro Tactical SPX, offering a rigid, heat-resistant design with integrated M-LOK mounting slots for accessories. Controls are optimized for confident operation and include a knurled charging handle, oversized paddle-style bolt release, and an optimized tang-mounted safety.
Optics-Ready
Further distinguishing the SPX, the 990 Aftershock SPX features the same optic-ready receiver cut as the 940 Pro Tactical SPX, allowing for direct mounting of micro-dot optics. A winged front fiber optic sight completes the sighting system, delivering fast target acquisition and seamless optic compatibility.
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Ergonomics That Work
The exterior design reflects Mossberg’s focus on ergonomic efficiency and tactical performance. The black synthetic Aftershock grip provides a secure, comfortable hold and features a rubberized palm pad to reduce felt recoil, along with an integrated quick-detachment sling cup. Complementing the grip, the SPX handguard maintains a streamlined profile while delivering exceptional durability.
Dialed-In Specs, No Compromises
Completing the 990 Aftershock SPX are 14.75-inch or 18.5-inch Accu-Chok barrels, 5+1 capacity with 2.75-inch shotshells, and a choice of matte blue metal or Cerakote finishes.
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Mossberg continues to deliver innovation, reliability, and exceptional tactical performance with the 990 Aftershock SPX— a premium defensive tool that blends compact handling with modern tactical capability.