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GEISSELE AUTOMATICS
AR-15/M16 MK 4 SUPER MODULAR RAILS, M-LOK

854014005717 100015366

Description
Ratings (6)

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.

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Customer ratings for GEISSELE AUTOMATICS 13.5" SUPER MODULAR RAIL MK4 M-LOK BLACK

Number of ratings: 6
From brownells.com: 6
Average rating: 4.8

Awesome Rail! (05/10/2016)

The fit is awesome and I could not be happier. Keep in mind the DDC color varies pretty widely, so be prepared to get a color that likely won't match other coatings. Mine came in a medium brown color.

Big plus getting a free low profile gas block at this price also.

<img width="500" src='/userdocs/reviewimages/3a7831e4-20c1-4af4-9916-0befdecbc8dc.jpg' alt=''>

<img width="500" src='/userdocs/reviewimages/04f40c14-8df0-4c3c-bb97-6c645197e5fd.jpg' alt=''>

Awesome Rail! (05/10/2016)

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.

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.

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.

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.

Read 6 more ratings on brownells.com

339.9 409.9 7 GBP

Product no.: 100015366
GEISSELE AUTOMATICS 13.5" SUPER MODULAR RAIL MK4 M-LOK BLACK
Mfr Part: 05-278B 854014005717 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.

374.9 GBP 0 £374.90 *

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

Specs: Color: Black Length: 13.5 Make: AR-15 Material: Aluminum Style: M-LOK Type: Drop-In

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Top takeaways

The Super Modular Rail MK4 M-LOK is a lightweight rail system with integrated M1913 picatinny sections at key positions for accessory attachment.
It features extensive venting for heat dissipation, contributing to its light weight without compromising strength and rigidity.
The rail has M-LOK slots on the 3, 6, and 9 o'clock positions, as well as the upper 45° quadrants for versatile accessory mounting options.

Attributes

Colour: Black Length: 13.5 Make: AR-15 Material: Aluminum Style: M-LOK Type: Drop-In Delivery weight: 0.676kg Shipping height: 127mm Shipping width: 127mm Shipping length: 381mm UPC : 854014005717

Item details

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

Product no.: 100017389
GEISSELE AUTOMATICS MK 4 15" M-LOK SUPER MODULAR RAIL, BLK
Mfr Part: 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.

409.9 GBP 1 £409.90 *

Delivery time approx. 7-14 days.
1 pcs. in the USA warehouse

Specs: Color: Black Length: 15 Make: AR-15 Material: Aluminum Style: M-LOK Type: Drop-In

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Product no.: 100015365
GEISSELE AUTOMATICS 9.3" SUPER MODULAR RAIL MK4 M-LOK BLK
Mfr Part: 05-283B 854014005694 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.

339.9 GBP 5 £339.90 *

Delivery time approx. 7-14 days.
5 pcs. in the USA warehouse

Specs: Color: Black Length: 9.3 Make: AR-15 Material: Aluminum Style: M-LOK Type: Drop-In

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Product no.: 100018960
GEISSELE AUTOMATICS MK4 9.3" M-LOK SUPER MODUALR RAIL DDC
Mfr Part: 05-283S 854014005700 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.

379.9 GBP 3 £379.90 *

Delivery time approx. 7-14 days.
3 pcs. in the USA warehouse

Specs: Color: DDC Length: 9.3 Make: AR-15 Material: Aluminum Style: M-LOK

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Product no.: 100018961
GEISSELE AUTOMATICS MK4 13.5" M-LOK SUPER MODULAR RAIL DDC
Mfr Part: 05-278S 854014005724 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.

409.9 GBP 5 £409.90 *

Delivery time approx. 7-14 days.
5 pcs. in the USA warehouse

Specs: Color: DDC Length: 13.5 Make: AR-15 Material: Aluminum Style: M-LOK

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Product no.: 100042897
GEISSELE AUTOMATICS MK4 10.5" M-LOK SUPER MODULAR RAIL DDC
Mfr Part: 05-1656S 810081130080 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.

399.9 GBP 6 £399.90 *

Delivery time approx. 7-14 days.
6 pcs. in the USA warehouse

Specs: Color: DDC Length: 10.5 Make: AR-15 Material: Aluminum Style: M-LOK Type: Drop-In

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Product no.: 100042896
GEISSELE AUTOMATICS MK4 10.5" M-LOK SUPER MODULAR RAIL BLACK
Mfr Part: 05-1656B 810081130097 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.

369.9 GBP 0 £369.90 *