Knights Armament Free Float RAS MK12 Mod1 Rail

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MSRP: $419.99
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The Knights Armament Free Float RAS has more than proven itself on the battlefield; famously used on Naval Special Warfare Command's Mk12 Mod1 special purpose rifle. The RAS (Rail Adapter System) features full length 12-inch mil-spec M1913 picatinny rails at the 12, 3, 6, and 9 o’clock positions, making it compatible with a variety of rail-mounted tactical accessories. The rail free floats the barrel, allowing for consistent barrel harmonics upon firing, and increased accuracy potential. 

The Knight's Free Float RAS is compatible with rifle, carbine and mid length gas systems and requires use of a low profile gas block. Disassembly of the rifle’s gas system and removal of the factory barrel nut will be necessary. This forend uses a proprietary barrel nut that may be installed using a standard AR-15 armorer’s barrel nut wrench (sold separately). For AR15 / SR15 based platforms only. Installation instructions are included. 

Includes three KAC 11 Rib Rail Panels.


  • Free Float
  • Installs in minutes
  • Four MIL-STD Picatinny rails at 12, 3, 6, and 9 o'clock
  • Includes 3x Rail Protection Panels
  • Compatible with carbine, mid or rifle length gas systems


  • Weight: 1 lb
  • Length: 12"
  • Machined from 6061/T651 Aircraft Grade Aluminum
  • Mil-Spec hard coat anodized
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1 Review

  • 5
    Awesome for the task

    Posted by Anonymous on 25th May 2019

    This is absolutely required if you want to build a replica of the Naval Special Warfare Command's Mk12 Mod1 special purpose rifle. Don't forget the wrench if you don't already have one.

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