M400 SDI XSeries | 16"

SIG SAUER M400 SDI XSeries 16" .223 Rem

The SIG SAUER M400 SDI XSERIES offers a wealth of features and upgrades for the M400 platform, making it an advanced, high-performance rifle.

The SIG SAUER M400 SDI XSeries lower receiver features fully ambidextrous controls, including the bolt catch and release, mode selector, charging handle, and magazine release. Another unique feature of the XSERIES is the precision-machined, flash-cut upper and lower receivers with a handguard clamping system that minimizes flex when using mounted accessories. Additional features include a hybrid muzzle brake/compensator, a 2-stage Matchlite trigger, and a Magpul SL telescoping stock.

TREAD brand accessories, available for separate purchase, include

M-LOK handguard with weight-reducing cutouts, available in 13" and 15" lengths;

3-chamber compensator;

Ambidextrous loading handle made of aircraft-grade aluminum with a dual roll-pin design;

ROMEO5 sight with a 2MOA dot featuring ten brightness settings, MOTAC, and a 50k battery life;

Folding sights and front and rear sights, easy to install, adjustable, and ready for use in a flash;

M-LOK front sight adapter with co-witness height made of lightweight aluminum;

Multiple configurations of M-LOK grip kits made of high-strength polymer;

Factory-upgraded, single-stage trigger with a flat blade.