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    AT3™ PROMOD-K Keymod AR-15 Free Float Handguard

    The AT3 PROMOD-K is a lightweight, durable, and easy-to-install Keymod AR-15 handguard at a price that won’t break the bank.

    The slim free-float design adds minimal weight while enhancing accuracy by keeping stress off the barrel. With its simple clamp-on design and 10”, 12” or 15” lengths, the PROMOD-K is the perfect upgrade for your existing rifle, or the centerpiece of your next AR-15 build.

    Lightweight & Durable

    • Unique lightweight, slim design with Keymod attachment points at the 3, 6, 9, & 12 o’clock positions
    • Rock-solid 6061 aircraft aluminum handguard that withstands the harshest treatment
    • Top rail aligns with AR-15 flat-top upper receivers for perfect alignment of optics, iron sights, and other accessories
    • Handguard clamps securely onto the included steel barrel nut using steel mounting hardware to assure a secure fit with zero movement
    • Backed by the AT3 Lifetime Warranty

    Impeccable Fit and Finish

    • Stealthy matte-black anodized finish provides a durable corrosion-resistant surface that matches your existing parts.
    • Precision CNC milled Keymod and MIL-STD-1913 (Picatinny) rail slots assure proper fit for all your accessories
    • Machined vent holes reduce weight and keep the handguard cool, even after a long day at the range.
    • One 5-slot Keymod-to-Picatinny rail section included

    Easy Installation

    • Simply install the barrel nut to the proper spec and clamp on the handguard – no “timing” or shims required.
    • Easily upfit your handguard with Keymod accessories – compatible with all Keymod products including rail sections, forward grips, rail panels, and more.
    • Installation questions? Check out the installation instructions for the PROMOD-K handguard

    IMPORTANT NOTEthe included barrel nut requires a 29mm or 1 3/16" wrench (not included). We recommend using a standard 8” length crescent wrench, 29mm or 1 3/16" box wrench, or 29mm / 1 3/16" crowfoot with torque wrench.

    More Information

    • Full kit - includes all mounting hardware and 1 Keymod 5-Slot Rail section – all included parts pictured below
    • Most rifle setups will require the use of a low profile gas block that sits under the handguard.

    Included in the box:

    • Handguard with steel barrel nut and all mounting hardware
    • 5-slot keymod-to-picatinny rail
    • Hex wrenches for handguard and rail sections

    AT3™ PROMOD-K Keymod AR-15 Free Float Handguard Hardware Grande


    • Rifle Type: AR-15 (If you have a .308 AR variant, check out our AR-10 / .308 page)
    • Material: 6061 Aircraft Aluminum
    • Included Rail Section: One Piece Aluminum Picatinny Rail Section - 3 3/8” Length, 5 slots
    • Finish: Hard-coat anodized (matte black)
    • Handguard inside diameter: 1 5/16”
    • Barrel nut inside diameter: 1.02” (compatible with barrels up to 1” diameter)
    • Weight:
      • 10" Handguard – 5.4oz (handguard only) / 9.7oz (handguard + barrel nut)
      • 12" Handguard – 6.1oz (handguard only) / 10.4oz (handguard + barrel nut)
      • 15" Handguard – 7.3oz (handguard only) / 11.6oz (handguard + barrel nut)

    Frequently Asked Questions:

    Will this fit my AR-15?

    This handguard will work with the majority of mil-spec AR-15’s on the market. In most instances, it will also require the use of a low-profile gas block that fits underneath the rail.

    This product will not work with non milspec upper receivers like the Bushmaster Carbon due to the non-standard barrel threads, and it is not compatible with most piston kits as they won’t fit under the handguard.

    We’re always glad to verify the fit for your rifle, just contact us! And if it doesn’t fit, we are glad to return it for you. And if you’re new to AR-15, we recommend watching a couple of the videos on our installation video page to understand how the process works.

    What tools and additional parts are required?

    For parts - most setups will require a low profile gas block.

    For tools - we recommend:

    • A vise and non-marring vise block for holding the upper
    • A 29mm wrench (an 8” crescent wrench will work, or a 29mm box wrench, or 29mm crowfoot wrench with torque wrench)
    • A torque wrench can be also be used to assure you stay in the AR-15 barrel nut torque range (30-80 ft lbs). Since this range is quite wide, is torque wrench may not be needed, but is recommended if you're not experience in torquing AR-15 barrel nuts.

    AT3™ PROMOD-K Keymod AR-15 Free Float Handguard

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      Customer Reviews

      Based on 6 reviews
      Great hand guard

      Put this on my first AR build. And it’s way lighter then I expected. Also feels great in my hand! Would not hesitate to buy another one!


      Have not put on rifle yet still getting parts but finish was excellent, shipped on time , packaged well can’t wait to get completed and run it

      Good functional Handguard

      Easy install, excellent fit and finish, matches well. The provide extra rail, when attached to top of the Forearm is higher then the 2 rails built into the forearm, disappointing. Edges around attachment holes are really crisp to sharp in some areas. Still would recommend unit. Works perfectly.

      Highly Recommended

      Nice lightweight rail. Great price. Fit perfectly on a left hand Stag Arms AR.

      We are glad to hear this was a good setup for your left handed AR.
      Great handguard

      This is the second one of these I've purchased. It's extremely lightweight and I love the look.

      They changed the design somewhat on this latest one though. The top rail no longer extends the length of the guard and they now only include ONE of the rail section pieces (my first one came with three or four) and the price is about $10 higher. That's all pretty disappointing.

      Lastly, I really wish this came in FDE.

      We are glad to hear that you are pleased with some of the designs of the new keymod handguard. We will look into your comments for future designs.