Aero 11.4 Mod 4 Handguard Kb

The Aero Precision 11.4 Mod 4 handguard is a precision-engineered free-float rail built for AR-15 rifles that demand accuracy and modularity without compromise. At 11.4 inches, it strikes a balance between handiness and mounting real estate—ideal for mid-length builds, tactical setups, and shooters who want enough M-LOK interface to attach optics, lights, and accessories without excess rail weight. Machined from 6061-T6 aluminum, the MOD 4 minimizes point-of-impact shift and deflection under load, making it a solid choice for both range work and field use.

What sets the MOD 4 apart is attention to real-world durability. The steel barrel nut seats without timing, so installation is straightforward and doesn't require specialty tools. The lug pattern matches mil-spec castle nuts, keeping your build compatible with standard AR-15 components. Four steel-reinforced QD sockets resist wear from repeated sling attachment, and two anti-rotation set screws keep the handguard locked in place on mil-spec and Aero M4E1 upper receivers alike. The full-length seven-sided M-LOK surface gives you flexibility to set up your rifle your way.

An 1.2-inch internal diameter accommodates low-profile gas blocks, so you're not limited to oversized front sight blocks if you're running a short-stroke or adjustable piston system. You get the handguard, barrel nut, and mounting hardware in the box—everything needed to install and go to work.

Key Features

• 6061-T6 aluminum construction engineered for minimal deflection
• Steel barrel nut and reinforced QD sockets for field durability
• Full-length 7-sided M-LOK interface for accessory customization
• No-timing barrel nut installation—no specialty tools required
• Compatible with mil-spec AR-15 and Aero M4E1 upper receivers
• Two anti-rotation set screws for secure, consistent fit
• Low-profile gas block clearance

Specifications

Frequently Asked Questions

What AR-15 uppers does the 11.4 MOD 4 fit?

The MOD 4 is designed to match seamlessly with Aero Precision M4E1 Threaded Upper Receivers and the PRO series. It is also compatible with mil-spec AR-15 upper receivers.

Does this handguard work with a low-profile gas block?

Yes. The 1.2-inch internal diameter is compatible with low-profile gas blocks, so you have flexibility in your gas system choice.

Do I need special tools to install the barrel nut?

No. The barrel nut lug pattern matches mil-spec castle nuts, so you can install it with standard AR-15 tools. The design eliminates the need for timing, making installation straightforward.

What comes in the box?

You receive the MOD 4 handguard, the MOD 4 barrel nut, and mounting hardware. Two anti-rotation set screws are included to secure the handguard on your upper receiver.