Geissele MK4 Super Modular Rail 9.3" M-LOK Desert Dirt AR-15

The Geissele Automatics Super Modular Rail MK4 delivers precision-grade rigidity and modularity for serious AR-15 builds. This 9.3-inch handguard transforms standard carbine platforms into versatile tactical systems capable of supporting optics, lights, and accessories without compromising barrel harmonics.

What Makes This Different

Geissele's proprietary barrel nut system creates a true free-float design that eliminates contact between the handguard and barrel. The MK4 uses continuous top rail construction machined from 6061-T6 aluminum, providing 40% more rigidity than standard two-piece designs. Desert Dirt Type III hard coat anodizing resists wear and corrosion while maintaining consistent torque specifications across temperature extremes.

Key Features

• True free-float design with proprietary barrel nut system
• M-LOK attachment points at 3, 6, and 9 o'clock positions
• Continuous Picatinny top rail machined from single billet
• 9.3-inch length accommodates carbine gas systems with clearance
• Desert Dirt Type III hard coat anodized finish
• Anti-rotation tabs prevent handguard movement under stress
• Compatible with standard AR-15 upper receivers

Field testing demonstrates the MK4's ability to maintain zero through rapid temperature changes and sustained fire schedules. Law enforcement agencies report consistent accuracy improvements when upgrading from standard plastic handguards. The M-LOK interface accepts modern accessories while reducing overall system weight compared to quad-rail alternatives. Competitive shooters benefit from the enhanced stability during precision shooting sequences.

Technical Specs

• Length: 9.3 inches
• Weight: 10.6 ounces
• Material: 6061-T6 aluminum construction
• Finish: Desert Dirt Type III hard coat anodized
• Attachment: M-LOK slots at 3, 6, 9 o'clock positions
• Top rail: Continuous Picatinny MIL-STD-1913
• Compatibility: Standard AR-15 upper receivers
• Included: Proprietary barrel nut and installation hardware
• Country of origin: Made in USA

The MK4 represents Geissele's commitment to manufacturing precision components that exceed military specifications. Professional users choose this handguard when accuracy and reliability cannot be compromised. Installation requires proper torque specifications and thread preparation for optimal performance.