The FN SCAR’s factory rail system is notoriously bulky, uncomfortable to grip bare-handed, and forces tactical accessories high off the receiver axis. Standard extended rails add support length, but leaving full-length Picatinny along the top spine adds unnecessary weight and creates snag points for slung gear.

Officially licensed by Kinetic™ Development Group, the PTS SCAR MREX™ MK2 4.25” Rail completely overhauls your rifle's front-end geometry. Precision machined from 6000-series aluminum, it weighs just 192 grams while providing a massive 4.25-inch extension forward of the front sight/gas block. The MK2 configuration eliminates the top 12 o'clock Picatinny rail entirely, replacing it with continuous M-LOK slots. Combined with added M-LOK positions at 2 o'clock and 10 o'clock, you can tuck tactical lights and IR illuminators closer to the barrel bore than ever before, creating an ultra-clean, low-profile setup tailored for a modern C-clamp grip.

Key Features & Technical Highlights

• Replaced 12 O'Clock Picatinny with Full M-LOK: Strips away bulky 1913 rails on top to create a flat, continuous M-LOK channel for lower-profile switch and optic/laser mounting.
• Extended 4.25" Real Estate: Adds over 4 inches of support space past the gas block, accommodating extended arm reach for faster target indexing and muzzle control.
• MK2 2 & 10 O'Clock M-LOK Channels: Added angular mounting slots allow weapon lights to sit tight against the gas block shield, reducing broadside snag risks.
• One-Piece 6000-Series Aluminum Construction: Delivers rugged durability for hard field use while keeping added front-end weight down to only 192g.
• Integrated Anti-Rotation QD Mounts: Built-in sling sockets on both sides keep two-point slings from twisting or wrapping under high movement.

Technical Specifications

• Brand: PTS Syndicate (Fully licensed by Kinetic™ Development Group)
• Product Name: SCAR MREX™ M-LOK™ MK2 4.25” Rail
• SKU / Part Numbers: KN013490307 (Black) / KN013490313 (Dark Earth)
• Material: 6000 Series Aluminum  
• Dimensions: 284 (L) x 55 (W) x 54 (H) mm  
• Weight: Approx. 192g  
• Platform Compatibility:
  • Cyber Gun SCAR-H (GBB)  
  • VFC SCAR-H (AEG & GBB) / SCAR-L (AEG)  
  • Tokyo Marui Recoil Shock SCAR-H / SCAR-L  
  • ARES SCAR Series

Operational Applications

• Mid-to-Long Range SCAR Builds: Perfect extension for standard-length barrels, providing optimal hand-placement ergonomics without ruining weapon balance.
• Sleek Low-Profile Accessory Rigging: Mount pressure pads and lights directly to top/angled M-LOK slots without needing tall Picatinny adapters.