The Maxim Defense SDX RFLX is a .300 BLK integrally suppressed AR-platform firearm built around the SDX508 system, 8.5" barrel, over-the-barrel M-Kore RFLX suppressor, SDX 2-piece M-LOK handguard & full-length 1913 top rail. Available as a pistol or SBR, it is designed for compact suppressed use, maneuverability & reduced added muzzle length. The SDX RFLX is engineered as a complete suppressed system rather than a rifle with a can awkwardly bolted on after the fact. Maxim Defense’s reputation for premium PDW-style platforms, compact stocks, braces & suppressor integration shows here with tuned gas operation, ALG Combat trigger, military-grade materials & 129 dB listed performance at the shooter’s ear with subsonic ammunition, which is impressively quiet.