Sig Sauer RM400-SDI-16B-FDE M400 SDI XSeries 5.56 NATO 16" 1:7" FDE Rifle w/M-LOK Handguard & (1) 30rd MagThe Sig Sauer M400 SDI XSeries is a 5.56 NATO semi-automatic rifle designed for performance, reliability, and versatility. Sig Sauer RM400-SDI-16B-FDE features a 16-inch barrel with a 1:7" twist rate, optimized for stabilizing a wide range of bullet weights. Built with fully ambidextrous controls, including a unique ambidextrous bolt catch and release, the M400 SDI X ensures smooth operation for both left- and right-handed shooters. Its free-floating M-LOK handguard features a steel lockup system, enhancing rigidity and minimizing deflection for improved accuracy when mounting accessories. The rifle includes a 2-Stage Matchlite Duo trigger with a 4.5 - 6.5 lb pull weight for a crisp and consistent break. Finished in Flat Dark Earth, the M400 SDI X is built for durability and reliability in demanding conditions. It comes with one 30-round magazine for optimal capacity..yellow-box p {font-size:16px}.special-tab {color: #FFFFFF}The Sig Sauer M400 SDI XSeries was developed in collaboration with the expert instructors at SIG SAUER Academy, drawing on decades of experience and hands-on training. Engineered to exceed the highest standards of performance and reliability, this rifle is built for both professional and enthusiast shooters. Featuring fully ambidextrous controls, including a unique M400-SDI lower receiver with an ambidextrous bolt catch and release, the Sig Sauer M400 SDI XSeries Rifle ensures seamless operation for both left- and right-handed shooters. This design also enhances transitional shooting, making it more intuitive and efficient in dynamic environments. The free-floating handguard incorporates a steel lockup system that drastically reduces deflection, providing maximum rigidity and ensuring that mounted accessories on all four sides have zero impact on accuracy. At the heart of the rifle is the 2-Stage Matchlite Duo trigger, delivering a crisp, precision feel with a 4.5 - 6.5 lb pull weight and a flat-blade design for enhanced control. To maximize durability and reliability, the M400-SDI X is coated with high-performance finishes, ensuring long-lasting performance in the harshest conditions. Features of the Sig Sauer M400 SDI XSeries: Available with a Moss Green Cerakote, FDE Cerakote, or Black Anodized FinishAmbidextrous Bolt Catch and ReleaseCompensator/Flash HiderDual Clamp Handguard Locking System for Reduced DeflectionLow-Profile Gas Block with Mid-Length Gas SystemSIG 2-Stage Matchlite Duo TriggerMagpul SL Stock Sig Sauer M400 SDI XSeries 5.56 NATO 16" 1:7" Bbl FDE Rifle w/M-LOK Handguard & (1) 30rd Mag RM400-SDI-16B-FDE