Sig Sauer M400 556 Nato W/ Romeo5 Gen II & Foxtrot MSR SDI Sentry Rifle Package RM400-SDI-16B-R5FX

Sig Sauer M400 SENTRY SDI 5.56 NATO – ROMEO5 Gen II, FOXTROT-MSR Light, Vertical Grip

The Sig Sauer M400 SENTRY SDI offers a ready-to-roll tactical solution straight out of the box. Chambered in 5.56x45mm NATO and built on the battle-proven M400-SDI X platform, this semi-automatic rifle combines reliability, versatility, and precision with factory-installed upgrades, including a ROMEO5 Gen II red dot sight, FOXTROT-MSR Full Size weapon light, and a vertical foregrip for enhanced control.

Designed with direct feedback from professional instructors at SIG SAUER Academy, the M400 SENTRY is engineered for shooters who demand performance without compromise. Featuring a 16" chrome moly steel barrel with a 1:7 twist rate, a mid-length direct impingement system, and a free-floating M-LOK/Picatinny handguard, the SENTRY delivers superior handling, accuracy, and modularity for home defense, training, or recreational shooting.

Topping off the package, the ROMEO5 Gen II red dot provides a crisp 2 MOA aiming point with motion-activated MOTAC™ technology and over 40,000 hours of runtime. The included FOXTROT-MSR light blasts 1,250 lumens and 33,000 candela to dominate low-light conditions. With a total package weight of just 8 lbs, the M400 SENTRY is built for serious work—no upgrades needed.

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