Description, Features & Specifications

Description

The SIG SAUER M400 SDI 10" M-LOK Handguard is a genuine factory replacement designed specifically for the SIG M400 SDI X and TREAD platforms, while maintaining full compatibility with standard AR-15 mil-spec builds.

Machined from lightweight aluminum and finished in durable black anodizing, this free-float handguard improves accuracy by eliminating barrel contact during supported or rested shooting. Integrated M-LOK slots along the sides and bottom allow easy mounting of lights, grips, and accessories, while the M1913 Picatinny top rail supports optics and iron sights with a continuous, rigid mounting surface.

Strategic lightening cuts reduce overall weight without sacrificing strength, keeping the rifle balanced and maneuverable. Whether you’re restoring a factory SIG rifle or upgrading a custom AR-15 build, this handguard delivers factory-correct fit, clean aesthetics, and proven performance.

This kit includes the barrel nut, clamps, and installation hardware, making it a complete drop-in solution for compatible rifles.

Key Features & Benefits

  • Genuine SIG SAUER factory M400 SDI X handguard

  • Free-float design improves accuracy and consistency

  • M-LOK slots on sides and bottom for modular accessories

  • M1913 Picatinny top rail for optics and sights

  • Lightweight aluminum construction with lightening cuts

  • Durable black anodized finish

  • Complete kit includes barrel nut, clamps, and screws

  • Compatible with standard AR-15 mil-spec platforms

Included in the Box

  • SIG SAUER M400 SDI 10" Handguard

  • Barrel Nut

  • Barrel Clamps

  • (2) Mounting Screws

  • Installation Hardware

Description

The SIG SAUER M400 SDI 10" M-LOK Handguard is a genuine factory replacement designed specifically for the SIG M400 SDI X and TREAD platforms, while maintaining full compatibility with standard AR-15 mil-spec builds.

Machined from lightweight aluminum and finished in durable black anodizing, this free-float handguard improves accuracy by eliminating barrel contact during supported or rested shooting. Integrated M-LOK slots along the sides and bottom allow easy mounting of lights, grips, and accessories, while the M1913 Picatinny top rail supports optics and iron sights with a continuous, rigid mounting surface.

Strategic lightening cuts reduce overall weight without sacrificing strength, keeping the rifle balanced and maneuverable. Whether you’re restoring a factory SIG rifle or upgrading a custom AR-15 build, this handguard delivers factory-correct fit, clean aesthetics, and proven performance.

This kit includes the barrel nut, clamps, and installation hardware, making it a complete drop-in solution for compatible rifles.

Key Features & Benefits

  • Genuine SIG SAUER factory M400 SDI X handguard

  • Free-float design improves accuracy and consistency

  • M-LOK slots on sides and bottom for modular accessories

  • M1913 Picatinny top rail for optics and sights

  • Lightweight aluminum construction with lightening cuts

  • Durable black anodized finish

  • Complete kit includes barrel nut, clamps, and screws

  • Compatible with standard AR-15 mil-spec platforms

Included in the Box

  • SIG SAUER M400 SDI 10" Handguard

  • Barrel Nut

  • Barrel Clamps

  • (2) Mounting Screws

  • Installation Hardware

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XTREME Superstore by HR Tactical Innovations

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SIG SAUER M400 SDI 10 Inch M-LOK Free-Float Handguard

$299.99
$299.99
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