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Geissele Automatics

Geissele Super Modular MK4 M-LOK AR-15 Handguard

Regular priceFrom $281.00 USD
Shipping calculated at checkout.

AR-15 free-float M-LOK handguard with 7000 Series aluminum, Type III anodizing, 1.35" inner diameter, barrel nut, and variant review.

Color:
Length

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⚠️ Sold for sporting and training applications. Customer is responsible for ensuring compliance with all applicable local laws and regulations. See Terms .

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🚚 Shipping & Delivery

Most in-stock items ship within 3 business days.

Special order items are typically processed within 14 business days (excluding weekends and holidays).

Custom items may require additional time depending on production schedules.

If you’d like to receive your order sooner, please select an expedited shipping option at checkout.

Some products ship directly from the manufacturer, and an equivalent carrier or service level will be chosen to match your selected shipping speed.

Shipping delays caused by carriers are outside our control, but we’ll always help track updates.

See our Shipping Policy for details.

🔄 Returns, Exchanges & Warranty

Returns are accepted within 14 days for items that are unused, unopened, and in original packaging with no damage.

A restocking fee applies, but it may be partially waived if store credit is selected instead of a refund to the original payment method.

Custom builds, sale items, and hazardous goods are final sale.

Warranty Coverage: Manufacturer warranties apply to all standard products. Any defects, malfunctions, or performance issues are handled directly by the manufacturer per their terms.

HR Tactical Innovations covers a Fitment & Functionality Guarantee on all custom or modified items — if a verified production error occurs, we’ll replace the item.

View our Refund Policy for full details.

🌍 International Shipping

We ship worldwide to Canada, Mexico, Europe, Asia, and Oceania, including:

🇨🇭 Switzerland • 🇨🇿 Czechia • 🇩🇪 Germany • 🇩🇰 Denmark • 🇪🇸 Spain • 🇫🇮 Finland • 🇫🇷 France • 🇬🇧 United Kingdom • 🇭🇰 Hong Kong SAR • 🇮🇪 Ireland • 🇮🇹 Italy • 🇯🇵 Japan • 🇰🇷 South Korea • 🇲🇾 Malaysia • 🇳🇱 Netherlands • 🇳🇴 Norway • 🇵🇱 Poland • 🇵🇹 Portugal • 🇸🇪 Sweden • 🇸🇬 Singapore • 🇦🇺 Australia • 🇳🇿 New Zealand • 🇦🇪 UAE and more.

Transit averages 2–4+ weeks depending on customs clearance. Delays caused by customs or local authorities are outside of our control. Faster transit times may be available through expedited shipping options, though this does not guarantee faster customs processing.

Import duties, VAT, taxes, and brokerage fees are not included in your order total and must be paid by the recipient.

Customers are responsible for ensuring that all items ordered comply with their country’s import laws and for obtaining any required permits or documentation prior to purchase. We do not provide guidance on country-specific import requirements.

If a package is rejected, unclaimed, or returned due to unpaid duties, missing documentation, import restrictions, or an incorrect address:

  • The order will be issued as store credit only
  • Original shipping costs are non-refundable
  • Any non-recoverable shipping or return fees may be deducted

If a shipment is lost, seized, or not returned, an insurance claim must be completed before any resolution is provided. If the claim is denied, no refund or credit will be issued.

Pressurized or restricted items will ship via ground services only where permitted.

For more information view our Shipping Policy and our Refund Policy.

Questions? Contact [email protected] before checkout.

🎖️ Military / GovX Discounts

⚙️ Product Details

The Geissele Super Modular MK4 Rail is an ultra-light, precision-machined free float handguard built specifically for the AR-15 platform. Designed for rigidity, repeatable zero retention, and modular flexibility, the MK4 delivers professional-grade performance without excess weight.

Machined from 7000 Series aluminum and finished in Type III hardcoat anodizing, this rail is built to handle serious use while maintaining a refined, streamlined profile.


Precision Free Float Design

Proprietary Barrel Nut System
The included barrel nut increases surface contact between the rail and upper receiver, enhancing rigidity and improving accuracy and repeatability if the handguard is removed for maintenance.

True Free Float Platform
Eliminates pressure on the barrel, allowing consistent harmonics and improved accuracy potential.


Advanced Mounting System

M-LOK on Five Surfaces
Accessory slots run along five sides of the rail, allowing flexible placement for lights, grips, bipods, and mission-specific equipment while promoting airflow for cooling.

Full-Length M1913 Picatinny Top Rail
Continuous top rail supports optics, backup irons, and night vision devices.

Integrated Front Rail Sections
M1913 sections at the 3, 6, and 9 o’clock positions near the muzzle allow solid mounting of weapon lights and bipods.


Lightweight Strength

7000 Series Aluminum Construction
Engineered for durability while keeping weight minimal.

Type III Hardcoat Anodized Finish
Available in Black and Desert Dirt Color (DDC) for corrosion resistance and long-term durability.

9.3" Model Weight
11.0 oz (weight varies slightly by length).


Available Configurations

Black
9.3"
10"
13.5"
15"

Desert Dirt Color (DDC)
9.3"
13.5"
15"


Ideal For

Duty rifle builds
Competition AR setups
Precision-focused builds
Modular tactical platforms

Specifications

  • Material
    7000 Series Aluminum
  • Color / Finish
    Type III Hardcoat Anodized
  • Included Components
    Proprietary barrel nut
  • Platform Compatibility
    Mil-Spec AR
  • Mounting Interface
    M-LOK, Picatinny / 1913
  • Weight
    11.0 oz

Reviews & Questions (1)

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