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The Geissele MK4 M-LOK rail is ultra-lightweight, features integrated M1913 sections, and offers maximum venting for heat dissipation while maintaining strength.

GEISSELE AUTOMATICS MK 4 15" M-LOK SUPER MODULAR RAIL, BLK

854014005731 100017389

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The Geissele MK4 M-LOK rail is ultra-lightweight, features integrated M1913 sections, and offers maximum venting for heat dissipation while maintaining strength.

AR-15/M16 MK 4 SUPER MODULAR RAILS, M-LOK - MK 4 15" M-LOK SUPER MODULAR RAIL, BLK

419.9 GBP 0 £419.90 *

Backorderable

Color: Black Length: 15 Make: AR-15 Material: Aluminum Style: M-LOK Type: Drop-In Product no.: 100017389

Backorderable

419.9 GBP 0 £419.90 *

-10 %

The Geissele MK4 M-LOK rail offers an ultra-lightweight design with integrated M1913 picatinny sections, maximum heat dissipation, and versatile accessory attachment.

AR-15/M16 MK 4 SUPER MODULAR RAILS, M-LOK - 13.5" SUPER MODULAR RAIL MK4 M-LOK BLACK

349.9 GBP 7 £349.90 * £389.90

In stock

Color: Black Length: 13.5 Make: AR-15 Material: Aluminum Style: M-LOK Type: Drop-In Product no.: 100015366

In stock

349.9 GBP 7 £349.90 * £389.90

-10 %

AR-15/M16 MK 4 SUPER MODULAR RAILS, M-LOK - MK4 9.3" M-LOK SUPER MODUALR RAIL DDC

349.9 GBP 6 £349.90 * £389.90

In stock

Color: DDC Length: 9.3 Make: AR-15 Material: Aluminum Style: M-LOK Product no.: 100018960

In stock

349.9 GBP 6 £349.90 * £389.90

-10 %

The Geissele MK4 13.5" M-LOK rail is ultra-lightweight, features integrated M1913 sections, and offers maximum venting for heat dissipation while ensuring modularity.

AR-15/M16 MK 4 SUPER MODULAR RAILS, M-LOK - MK4 13.5" M-LOK SUPER MODULAR RAIL DDC

379.9 GBP 1 £379.90 * £419.90

In stock

Color: DDC Length: 13.5 Make: AR-15 Material: Aluminum Style: M-LOK Product no.: 100018961

In stock

379.9 GBP 1 £379.90 * £419.90

-10 %

The Geissele MK4 M-LOK rail is ultra-lightweight, features integrated M1913 sections, maximum venting for heat dissipation, and versatile M-LOK slots for accessories.

AR-15/M16 MK 4 SUPER MODULAR RAILS, M-LOK - MK4 10.5" M-LOK SUPER MODULAR RAIL BLACK

344.9 GBP 7 £344.90 * £384.90

In stock

Color: Black Length: 10.5 Make: AR-15 Material: Aluminum Style: M-LOK Type: Drop-In Product no.: 100042896

In stock

344.9 GBP 7 £344.90 * £384.90

-10 %

The Geissele MK4 M-LOK rail is ultra-lightweight with maximum heat dissipation, offering modularity with M1913 sections and M-LOK slots for versatile accessory attachment.

AR-15/M16 MK 4 SUPER MODULAR RAILS, M-LOK - MK4 10.5" M-LOK SUPER MODULAR RAIL DDC

369.9 GBP 2 £369.90 * £409.90

In stock

Color: DDC Length: 10.5 Make: AR-15 Material: Aluminum Style: M-LOK Type: Drop-In Product no.: 100042897

In stock

369.9 GBP 2 £369.90 * £409.90

AR-15/M16 MK 4 SUPER MODULAR RAILS, M-LOK - 9.3" SUPER MODULAR RAIL MK4 M-LOK BLK

344.9 GBP 0 £344.90 *

Backorderable

Color: Black Length: 9.3 Make: AR-15 Material: Aluminum Style: M-LOK Type: Drop-In Product no.: 100015365

Backorderable

344.9 GBP 0 £344.90 *

344.9 419.9 7 GBP

419.9 GBP £419.90

Prices inclusive of duty & VAT.

Product no.: 100017389

Mfr. No.: 05-315B

854014005731 The Super Modular Rail MK4 M-LOK™ is Geissele’s ultra-lightweight 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 rails overall weight, while maintaining its same strong and rigid platform. The MK4 M-LOK rail features M-LOK slots at the 3, 6 and 9 o’clock positions as well as the upper 45° quadrants. This allows the user to keep the weight on the rail system down, while keeping the modularity and versatility to attach accessories as necessary. Barrel nut wrench & gas block not included.

Backorderable

10+

£419.90

Prices inclusive of duty & VAT.

10+

Backorderable, delivery time approx. 4-12 weeks from the USA warehouse.

100-Day Return Policy

Backorderable, delivery time approx. 4-12 weeks from the USA warehouse.

100-Day Return Policy

No charges until we ship

No charge:
Your credit card will not be charged when you place your order.

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You are under no obligation until the goods are shipped. You can cancel your order at any time before shipping - free of charge.

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Your credit card will only be charged once we ship your order. Not before.

Ultra-lightweight design
Integrated M1913 picatinny sections
Enhanced heat dissipation

Wish List Ask question

344.9 419.9 7 GBP

Description Specification Customers reviews Accessories

GEISSELE AUTOMATICS MK 4 15" M-LOK SUPER MODULAR RAIL, BLK

419.9 GBP £419.90

Prices inclusive of duty & VAT.

10+

£419.90

Prices inclusive of duty & VAT.

10+

Backorderable, delivery time approx. 4-12 weeks from the USA warehouse.

100-Day Return Policy

Description:

Discover the ultimate in lightweight modularity with the Geissele MK4 M-LOK Rail.

The Super Modular Rail MK4 M-LOK™ from Geissele Automatics is designed for those who demand performance without the added weight. This rail system is purpose-built to enhance your shooting experience.

Key Features:

Ultra-Lightweight Design: Maximizes performance while minimizing weight.
Integrated M1913 Picatinny Rail Sections: Located at the 3, 6, and 9 o’clock positions for versatile accessory attachment.
Optimized Venting: Provides maximum heat dissipation to maintain performance.
Modularity: M-LOK slots at 3, 6, 9 o’clock and upper 45° quadrants allow for customizable setups.

This rail system ensures that you can keep your setup lightweight while still enjoying the versatility to attach necessary accessories. Please note that the barrel nut wrench and gas block are not included.

Attributes

Colour:
```
Black
```
Length:
```
15
```
Material:
```
Aluminum
```
Style:
```
M-LOK
```
Type:
```
Drop-In
```
Weapon type:
```
AR-15
```
Delivery weight: 0.708kg
Shipping height: 102mm
Shipping width: 102mm
Shipping length: 483mm
UPC: 854014005731

Item details

Made in USA
US export classification: 0A501.y.1

Customers reviews

Customer ratings (6)

4.8 / 5

Recommended

Different Rail than pictured 01/11/2017

Got the rail in quicker than I thought. Good on Brownells for that. Although after looking at the rail it wasn't like its pictured. The one shown has a cut out where you can see the gas block. The one I received doesn't have that. Might just be a earlier generation. But either than that the rail looks good. And does what it supposed to do. Just be aware that you are not getting the one pictured.

Definitely recommended

Geissele 15" M-LOK hand guard 01/06/2017

Back In April I purchased a 13" M-LOK hand guard for a 16" barrel build. Liked it so much I bought a 15" for my 18" barrel build. Geissele makes "top notch" products and really transform a rifle build into something special and functional. I was able to take advantage of another Brownells Memorial Day weekend sale and save a bundle on the 15" MK4 hand guard. Thanks again for the great deal on a great product from Geissele.

Definitely recommended

Geissele 13" MK-4 M-LOK hand guard 25/04/2017

I was able to buy a Geissele 13" MK-4 hand guard during the recent sale Brownells had on all Geissele products (before they ran out of stock). I also bought a AR-15 reaction rod and Mil-Spec reaction block. Great tools to have if you are building AR-15's. The 13" MK-4 hand guard looks superb on my 16" SOCOM mid length barrel build. The Picatinny rails on the muzzle end of the hand guard at the 3,6 and 9 o'clock positions are a nice feature to add a bipod or sling attachment. I really like the barrel nut design because it doesn't require timing to install the gas tube (comes with it's own torque wrench). The stainless steel gas block that's included with this hand guard is a high quality addition too. Saved an additional $59 for a gas block. I'm adding a M-LOK Magpul 4.9" Picatinny rail to the bottom of the handguard to accept a Magpul angled hand grip. I have yet to find one reason not to recommend Geissele products. I saved a good amount of cash with the last sale Brownells had on Geissele products. Highly recommend the MK-4 hand guard or any other Geissele products. Oh yeah, I contacted Geissele directly on their web site (Sunday evening) to ask a few questions. They responded the very next morning. Very nice people to deal with.

Definitely recommended

Wrong part shipped 03/10/2016

I ordered this rail for a 16" mid-length upper. I received a 15" Mk8 instead. The Brownells inventory sticker says 13 Mk4, right beside the Geissele factory sticker which says 15" Mk8. This was my first time experiencing anything other than perfect service from Brownells. I installed the Mk8 anyway, which fits very well to my Seekins billet upper. The 15" rail stops just shy of the base of my brake, so attaching a QD suppressor overtop should be fine. The rail itself is of remarkable build quality and the rifle feels completely solid, I couldn't be happier with what Geissele is offering. Overall, while I don't mind the 15" vs. the 13" aesthetically, I would've preferred to have an integrated rail at the end for my bipod to attach. This means a little extra expense and hassle, but through no fault of Geissele's product. I hope this mix-up was merely an anomaly for those ordering this rail.

Variations:

AR-15/M16 MK 4 SUPER MODULAR RAILS, M-LOK - MK 4 15" M-LOK SUPER MODULAR RAIL, BLK

419.9 GBP 0 £419.90 *

Backorderable

Color: Black Length: 15 Make: AR-15 Material: Aluminum Style: M-LOK Type: Drop-In Product no.: 100017389

Backorderable

419.9 GBP 0 £419.90 *

-10 %

AR-15/M16 MK 4 SUPER MODULAR RAILS, M-LOK - 13.5" SUPER MODULAR RAIL MK4 M-LOK BLACK

349.9 GBP 7 £349.90 * £389.90

In stock

Color: Black Length: 13.5 Make: AR-15 Material: Aluminum Style: M-LOK Type: Drop-In Product no.: 100015366

In stock

349.9 GBP 7 £349.90 * £389.90

-10 %

AR-15/M16 MK 4 SUPER MODULAR RAILS, M-LOK - MK4 9.3" M-LOK SUPER MODUALR RAIL DDC

349.9 GBP 6 £349.90 * £389.90

In stock

Color: DDC Length: 9.3 Make: AR-15 Material: Aluminum Style: M-LOK Product no.: 100018960

In stock

349.9 GBP 6 £349.90 * £389.90

-10 %

AR-15/M16 MK 4 SUPER MODULAR RAILS, M-LOK - MK4 13.5" M-LOK SUPER MODULAR RAIL DDC

379.9 GBP 1 £379.90 * £419.90

In stock

Color: DDC Length: 13.5 Make: AR-15 Material: Aluminum Style: M-LOK Product no.: 100018961

In stock

379.9 GBP 1 £379.90 * £419.90

-10 %

AR-15/M16 MK 4 SUPER MODULAR RAILS, M-LOK - MK4 10.5" M-LOK SUPER MODULAR RAIL BLACK

344.9 GBP 7 £344.90 * £384.90

In stock

Color: Black Length: 10.5 Make: AR-15 Material: Aluminum Style: M-LOK Type: Drop-In Product no.: 100042896

In stock

344.9 GBP 7 £344.90 * £384.90

-10 %

AR-15/M16 MK 4 SUPER MODULAR RAILS, M-LOK - MK4 10.5" M-LOK SUPER MODULAR RAIL DDC

369.9 GBP 2 £369.90 * £409.90

In stock

Color: DDC Length: 10.5 Make: AR-15 Material: Aluminum Style: M-LOK Type: Drop-In Product no.: 100042897

In stock

369.9 GBP 2 £369.90 * £409.90

AR-15/M16 MK 4 SUPER MODULAR RAILS, M-LOK - 9.3" SUPER MODULAR RAIL MK4 M-LOK BLK

344.9 GBP 0 £344.90 *

Backorderable

Color: Black Length: 9.3 Make: AR-15 Material: Aluminum Style: M-LOK Type: Drop-In Product no.: 100015365

Backorderable

344.9 GBP 0 £344.90 *

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