Gauges: 12-ga., 2.75”. Barrels: 11.5” (Cyl. heavy-walled) NFA item. Introduced 2025. Enhanced assembly and quality control process with special finishes and features, including a refined loading port to help optimize performance. Other features: One-piece construction of the stand-off barrel, machined integrally to the barrel. Mossberg’s Aftershock bird’s head grip. 590M compatible magazines in 5-, 10-, 15-, and 20-round capacities.