The 590A1 M-LOK variant replaces the standard synthetic forend with an M-LOK compatible forend, allowing direct attachment of lights, lasers, and grip accessories without rail adapters. Retains all mil-spec 590A1 internals with the modern accessory-mounting interface. Type: Shotgun Action: Pump-Action Caliber: 12 Gauge Capacity: 9 Year introduced: 2018, USA Weight: 120 oz Overall length: 41" Status: Active Intended use: Law Enforcement, Home Defense, Tactical