Contract Knuckle Duster™ Kit

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Maximum Purchase:
1 unit

Product Overview

Final Chance to Purchase - This will be the final run of the Knuckle Duster Kit. Be sure to grab one while they are still available. 

Contract Knuckle Duster™ & RSB® Kit: - UK Contract overrun vertical grip kits designed for small constrainted weapons. These kits are comprised of our Knuckle Duster finger stop, which retroactively can be installed on any of our COG forend products, and our RSB vertical grip. Taking up only 1.5 M-LOK slots, this product was designed to allow a finger stop and vertical grip to be placed in the smallest footprint possible. Machined out of 6061 aluminum and finished with a type 03 mil-spec hard coat anodizing. Very limited amounts are available for commercial purchase. 

Limit 1 per person 

Fitment: These mounts will fit any M-LOK spec rails, these mounts are designed specifically for the Rattler/MCX/Virtus series M-LOK U-Rails (the non SD thinner OEM rail).

Ships Free and Made in USA

  • Mount Type: M-LOK
  • Footprint: 1.5-Slots
  • Height: 2.55"
  • Length: 2.50"
  • Weight: 2.33oz w/ hardware
  • Material: 6061 Aluminum
  • Finish: Type 03 Hardcoat Anodizing
  • Color: Carbon Black
  • Hardware: US Made 416 Stainless M-LOK Nuts
  • Fastener: US Made T20 Torx Fasteners w/ Nylon Thread Patch



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(2 reviews) Write a Review

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  • 5
    Contract Knuckle Duster

    Posted by Charlie F on Mar 13th 2024

    Fit perfectly on my Sig MPX K with the newer style hand guard. Finally found exactly what I was looking for. Railscale all the things!

  • 5
    Knuckle Duster Kit

    Posted by Miles de Mille on Mar 6th 2024

    Perfect addition to a Sig Rattler SBR.