HandguardsPremium

Kinetic Development Group

KDG SCAR MREX MkII 4.25 M-LOK Rail

Mid-length MREX MkII for FN SCAR 16/17 builds that need useful forward M-LOK space without the weight of the 6.5-inch rail.

KDG SCAR MREX MkII 4.25 M-LOK Rail

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Quick Specs

Price
$360
Weight
8.1 oz
Brand
Kinetic Development Group
Category
handguard

Features

  • •4.25-inch extension; 11.08 inches overall
  • •7 oz rail plus 1.1 oz mounting hardware
  • •6061-T6 aluminum
  • •Black Type III hardcoat or FDE Cerakote
  • •Fits FN SCAR 16 and 17

Capability Boosts

Modularity+2

Recommended For

Duty/Patrol+2
duty+2
Competition+2
customization+2

Compatibility Tags

family: modern-riflehandguard: mlokplatform: fn-scar-17splatform: fn-scar-16s

Overview

The MREX MkII 4.25 is the middle SCAR rail: enough length to move a light, laser, grip, or hand stop forward without committing to the 11-ounce installed weight of the 6.5. It measures 11.08 inches overall and weighs 7 ounces plus 1.1 ounces of mounting hardware.

KDG machines it from 6061-T6 aluminum for the FN SCAR 16 and 17. The black catalog SKU is MRX5-MK2-030, while FDE sibling MRX5-MK2-130 shares the selectable page. The separate 2.2 and 6.5 product pages are not interchangeable with this route.

Key Features

  • 4.25-inch mid-length MREX extension
  • M-LOK accessory mounting
  • 6061-T6 aluminum
  • Black and FDE variants
  • Dedicated SCAR 16/17 fitment

Pros

  • +Best balance of mounting space and installed weight
  • +Saves 2.9 ounces installed versus the 6.5-inch rail
  • +Exact black SKU is distinguished from the FDE sibling

Cons

  • −Costs the same as the longer 6.5-inch version
  • −Not for the SCAR 15P or SCAR 20S

Detailed Specifications

extensionLength
4.25 inches
overallLength
11.08 inches
weight
7 oz rail plus 1.1 oz mounting hardware
Material
6061-T6 aluminum
compatibility
FN SCAR 16 and SCAR 17
sku
MRX5-MK2-030 (black); MRX5-MK2-130 (FDE)

Compatible Platforms

FN

FN SCAR 17S

FN

FN SCAR 16S NRCH

Pairs Well With

Top matches

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Ruger Precision Rifle

1 shared compatibility tags

Great

Aero Precision

Aero Precision SOLUS Competition Rifle

1 shared compatibility tags

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Daniel Defense

Daniel Defense Delta 5 Pro

1 shared compatibility tags

Great

B&T

B&T APC223 PRO 420 mm

1 shared compatibility tags

Great

Sig Sauer

Sig MCX Virtus Patrol 16"

1 shared compatibility tags

Great

Sig Sauer

Sig MCX Spear-LT 11.5"

1 shared compatibility tags

Great

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