Aero Precision Apra600006C Mod 4 Handguard 9.1 Blk

The Aero Precision MOD 4 handguard is a precision-engineered rail system built for AR-15 shooters who demand stiffness, reliability, and versatility without compromise. Machined from 6061-T6 aluminum and secured with a steel barrel nut, this handguard is designed to minimize deflection under load and reduce point-of-impact shift—especially critical if you're running an infrared laser aiming device. Whether you're setting up a precision rifle, a tactical build, or a hunting AR, the MOD 4 delivers the rigid platform you need for consistent performance.

Installation is straightforward: the barrel nut requires no timing, and its lug pattern matches mil-spec castle nuts, so you won't need specialty tools. Two anti-rotation set screws provide redundancy and ensure a rock-solid fit, even with third-party upper receivers. The handguard ships with the barrel nut and mounting hardware, everything you need to get it on the gun.

Customization is built in. A full-length 7-sided M-LOK interface runs the length of the rail, letting you mount lights, grips, vertical foregrips, or other accessories exactly where you want them. The four steel-reinforced quick-disconnect sockets won't wear out with repeated use—a detail that matters if you rotate slings between rifles or run your gun hard. Internal diameter of 1.2" accommodates low-profile gas blocks, keeping your setup compact without sacrificing function.

The MOD 4 plays well with Aero's M4E1 Threaded Upper Receivers and PRO series components, but it's also compatible with any mil-spec AR-15 upper receiver, giving you flexibility in your build choices.

Key Features

• 6061-T6 aluminum construction engineered for stiffness and minimal deflection
• Steel barrel nut reduces point-of-impact shift under load
• Full-length 7-sided M-LOK interface for unlimited accessory mounting
• Four steel-reinforced quick-disconnect sockets for durable sling attachment
• Two anti-rotation set screws for secure, repeatable fit
• No timing required at barrel nut; uses standard mil-spec lug pattern
• Compatible with low-profile gas blocks
• Barrel nut and mounting hardware included

Specifications

Frequently Asked Questions

What AR-15 upper receivers is this handguard compatible with?

The MOD 4 handguard is designed to pair seamlessly with Aero Precision's M4E1 Threaded Upper Receivers and PRO series components. It's also fully compatible with any mil-spec AR-15 upper receiver, giving you broad compatibility across different builds and manufacturers.

Do I need special tools to install it?

No. The barrel nut requires no timing and uses a lug pattern that matches standard mil-spec castle nuts, so you can install it with common tools. The handguard comes with the barrel nut and all mounting hardware you'll need.

Can I use a low-profile gas block with this handguard?

Yes. The MOD 4 is designed to accommodate low-profile gas blocks, allowing you to maintain a clean, compact profile on your upper receiver.

What's included in the box?

Each MOD 4 handguard comes with the rail itself, the steel barrel nut, and mounting hardware. You'll have everything needed to install it on your upper receiver.