The M400-SDI X was designed to meet the highest standards of performance and reliability. From the rifle's full suite of ambidextrous controls to its proven mid-length gas system. Features fully Ambi Controls- safety, charging handle, bolt Catch & mag release; 2-Stage Matchlite Duo trigger; free floating M-LOK; mid-length direct impingement operating system and 6 position Magpul SL stock.
| Series | SDI-X |
| Model | M400 |
| Caliber | 5.56 NATO |
| Barrel Length Range | 16" to 16.99" |
| Gun Platform | AR-Style |
| Operating System | Direct Impingement |
| Stock Finish Group | Black |
| Capacity | 30+1 |
| Stock Material | Synthetic |
| Action | Semi-Auto |
| OAL | 33.25' - 36.50" |
| Hand | Ambidextrous |
| Sights | None |
| Barrel Finish | Black |
| Barrel Material | Chrome Moly Steel |
| Muzzle | Sig Flash Hider-Compensator |
| Twist | 1:7" |
| Receiver Description | Picatinny Rail |
| Magazine Type | AR-15 |
| Grips | Reduced Angle |
| Handguards | M-LOK |
| Height | 7.10" |
| Receiver Material | Aluminum |
| Safety | Lever |
| Thread Pattern | 1 / 2"x28 |
| Width | 2.75" |
| Stock Description | Magpul SL |
| Barrel Description | Threaded |
| Barrel Length | 16" |
| Max Capacity | 30 |
| Receiver Finish | Flat Dark Earth Cerakote |
| Trigger | Sig Two-Stage Matchlite Duo |
| Weight | 7 lbs |
| Stock Finish | Black |
| Handguard Finish | Flat Dark Earth |
