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Geissele Automatics MK4 Super Modular Rail – M-LOK Free Float Handguard with Picatinny Rails for AR 15

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Geissele Lifetime Warranty!
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Bomb-Proof M-LOK Handguard with Picatinny Rails for Ultra-Secure Mounting

Barrel Nut Wrench not included! Click here to purchase the required Geissele Barrel Nut Wrench.

The Super Modular Rail (SMR) MK4 M-LOK™ is Geissele’s lightweight yet rigid M-LOK option. These rails are purpose-built and feature integrated M1913 picatinny rail sections at the fore of the rail in the 3, 6 and 9 o’clock positions. Maximum venting for heat dissipation also dramatically reduces the rail’s overall weight, while maintaining its same strong and rigid platform. Utilizing Magpul’s M-LOK technology at the 3, 6, and 9 o’clock positions, as well as the upper 45 quadrants. The SMR MK4 is both versatile and modular, allowing the user to tailor their platform to his or her unique needs.

The SMR MK4 also features Geissele’s proprietary 2.25″ long barrel nut. This increases the surface contact where the rail interfaces with the receiver and creates a platform that can be trusted to be straight and true the entire length of the free float rail. This increases accuracy and zero repeatability during disassembly and reassembly when performing maintenance.

Specifications

  • Lengths Available:
    • 9.3″
    • 13.5″
    • 15″
  • Inside Diameter: 1.35″
  • Outside Diameter: 2.11″
  • Installed Weight:
    • 9.3″: 9.3 oz
    • 13.5″: 14.1 oz
    • 15″: 15.4 oz

Products available on this page:

The AT3 Tactical store has a 90 day no-hassle return policy for products in good condition. You can view the full details of our return policy here.

If you encounter an issue or defect with a product after 90 days of your purchase, you can refer to the manufacturer for a warranty claim. Their policies are below.

Geissele Limited Lifetime Warranty

  • Geissele Automatics warrants its firearms, components, and tools against defects in materials and workmanship during the lifetime of the product.
  • Geissele Automatics does not warrant against normal wear and tear, items consumed or expended by their normal use (including springs, pins, etc.), product misuse (including criminal misuse, negligence or use under the influence of drugs or alcohol), accidental damage, or damage caused by improper handling, unapproved modifications to the product, defective or improper ammunition, or corrosion.
  • Defective accessories (e.g., scopes, suppressors, flash hiders, sights, slings, parts with glass or electronic components, etc.) may be warranted by their original manufacturers but are not covered by this warranty.

If you submit a valid claim under this Limited Lifetime Warranty, Geissele Automatics will authorize your return of the product and, at its sole discretion, will:

  1. Repair the product, including replacement of defective parts with new or refurbished parts
  2. Replace the product with a product of equal or greater value.

If Geissele Automatics decides to replace a product under this warranty, Geissele will keep the product being replaced.

You must satisfy all terms and restrictions set forth in this Limited Lifetime Warranty and obtain a Return Material Authorization before shipping any product to Geissele Automatics.

Before shipping any product to Geissele Automatics, please ensure the following:

  1. The product has not been modified, is clean and any accessories have been removed (unless otherwise instructed by a Geissele Automatics technical support agent)
  2. There is no ammunition in any product or packaging
  3. The completed Return Material Authorization form has been placed inside the packaging
  4. The Return Material Authorization number has been clearly written on the outside of the packaging.

Any failure to follow these instructions could result in your package being refused and returned to you without repairs at your expense.

To obtain service, contact Geissele Automatics at sales@geissele.com or 610-272-2060.

Disclaimer: Manufacturer’s warranty is subject to change without prior notice.

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