The Maxim Defense SDX RFLX is a purpose-built integrally suppressed SBR system — not a rifle with a suppressor attached, but a single unified weapon engineered from the ground up as a complete suppressed platform — featuring the M-Kore over-the-barrel reflex suppressor that wraps back over the 8.5" .300 Blackout barrel to dramatically increase internal suppressor volume without adding length, delivering effective sound suppression with subsonic ammunition while maintaining reliable cycling and correct bolt velocity across both subsonic and supersonic loads. The M-Kore suppressor combines the low backpressure characteristics of a monocore design with the sound suppression performance of traditional M-baffle geometry, paired with a precision-tuned gas system and internal suppressor extension — all concealed within Maxim's two-piece M-LOK compatible Ledge handguard with full-length 1913 Picatinny top rail. Configured with the Maxim Gen 7 CQB stock on the SDX lower receiver and shipping with a 30-round magazine, this NFA SBR/suppressor combination requires two tax stamps and is built to the exacting standards Maxim Defense applies across its entire professional-grade firearm lineup.
- Manufacturer: Maxim Defense
- Model: SDX w/ RFLX Suppressor
- Caliber: .300 Blackout
- Capacity: 30 Rds
- Barrel / Suppressor: 8.5" Barrel, M-Kore Over-the-Barrel Reflex Suppressor
- Configuration: Maxim Gen 7 CQB Stock, SDX Receiver Set, (1) 30-Round Magazine Included
- Finish: Black
| __Barrel Length | 8.50" |
| __Action | Semi-Automatic |
| __Optic Footprint | Picatinny Rail |
| __Caliber | .300 Blackout |
| __Capacity | 30 |
| __Model | SDX w/ RFLX Suppressor |