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F4 Defense ARS-Lite Handguard - 13.6"

AR-15 Handguard


The F4 Adaptive Rail System Lite (ARS-L) is a purpose-built rail combining the functionality of the M1913 Picatinny rail and the adaptability of Magpul’s MLOK system. The ARS-Lite handguard features both, maintaining a seamless low profile and versatile configuration at the first 5 inches of the rail.  The middle of the rail is MLOK only.  We designed this feature to lower weight and place the MLOK only section in the area of the rail that does not typically field attachments. Our Patent Pending MLOK and Picatinny Adaptive Rail System (ARS) is directly integrated into the extruded profile of the rail, rather than a bulky quad rail configuration; built into the forward end of the rail that typically fields all attachments. No more adapter rails; accessories are attached directly to the rail. Strategic machining allows for maximum venting, air flow, and weight reduction while maintaining the structural integrity to maintain accuracy and repeatability. The barrel nut attachment system is the most user-friendly and effective system on the market. This modular system allows the flexibility to configure the rail based on the end-users individual preferences.


  • Material: Aerospace Grade 6061 T6 Aluminum
  • Functionality: Compatible with M-LOK and M1913 Picatinny accessories without the need of rail adapters.
  • Quick-Disconnect (QD) ports (3)
  • Length: 13.6 inches
  • Finish: Type III Hard Anodized
  • Additional MLOK slots at (4) 45° Positions for forward mounting lights, lasers, etc.
  • Barrel Nut Diameter: 1.378″
  • Barrel Nut: 7075 Aluminum Type III Hard Anodized Clear (Bronze Finish)
  • Anti-Rotation Tabs
  • 17-4PH Cored Stainless Steel Rail Mounting Attachment – Patent Pending by CMT
  • Barrel Nut Wrench Included
  • Weight: 9.68
  • American Made with American Metal

More Information
Product Type AR-15 Handguard
Manufacturer F4 Defense
Rail Length 13.6"
Mount M-LOK
Option AR-15
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