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  • ACT Advanced Combat Trigger by ALG Defense

    ACT Advanced Combat Trigger by ALG Defense

    Got an preference for AR builds reminiscent of those from a previous era? We do too. But like us, you're probably just not a fan of the mil-spec trigger. It's gritty and has a rough pull, and it generally feels like crap. But there's a way to keep that...

  • MOE+® Grip – AR15/M4 by Magpul

    MOE+® Grip - AR15/M4 by Magpul®

    The Magpul MOE+ Grip has a reinforced rubber mold wrapping around the polymer body, allowing for maximal comfort and weapon control. This durable material prevents snags and damage, allowing this product to be dependable in rugged environments. The MOE+...

  • M5 .308 Standard Lower Parts Kit by Aero Precision

    M5 .308 Standard Lower Parts Kit by Aero Precision

    If you plan to start an LR-308 build, you're gonna need a good lower parts kit. Aero Precision makes a lower parts kit designed for their M5, which is their own proprietarily designed .308 rifle that can also work with your LR-308 build, provided yours...

  • Spike's Tactical Pro Grip Spike's Tactical Pro Grip-2

    Spike's Tactical Pro Grip

    Replace that uncomfortable mil-spec grip on your AR with the Pro Grip by Spike's Tactical. It's got an ergonomically correct feel, and it's been shaped and contoured to fit your hand's natural grip to make your hand and your AR fit together like they're...

  • MOE+® EPT SBA3 Lower Build KIt

    MOE+® EPT SBA3 Lower Build KIt

    If you're building an AR-15 in pistol configuration, we can help you complete the lower half of your rifle while keeping you legal at the same time. To help with this, we've assembled this MOE+® EPT SBA3 Lower Build Kit. It comes with everything you...

  • Enhanced Lower Parts Kit by Strike Industries

    Enhanced Lower Parts Kit by Strike Industries

    If your .223 or 5.56mm AR-15's lower parts kit is worn out needs replaced, or if you just want to refresh the controls on your rifle, you need to get the Strike Industries Enhanced Lower Parts Kit. It'll rejuvenate your lower assembly and also has the...

  • AR-308 Lower Parts Kit - Spike's Tactical

    Spike's Tactical - AR-308 Lower Parts Kit

    The Spike's Tactical AR-308 Lower Parts Kit has a great fit and finish along with a military grade design that is built to last. This parts kit is meant to be used with Spike's Tactical's forged sets and may not be compatible with any other large frame...

  • PSA MOE SBA3 Lower Assembly Kit

    PSA MOE SBA3 Lower Build Kit

    Got your stripped lower and decided on making an AR-15 pistol, or maybe you want to change things up and convert your SBR into a pistol. Then check out this SBA3 lower assembly that features parts from popular and reliable brands. It includes Magpul MOE...

  • MOE-K2® Grip – AR15/M4 by Magpul MOE-K2® Grip – AR15/M4 by Magpul-2

    Magpul® MOE-K2® Grip - AR15/M4

    The Magpul MOE-K2 Grip offers a full size design that has a steeper vertical grip angle compared to the previous model, the MOE-K. With a steeper vertical grip angle, the shooter's hand is naturally positioned closer to the body which allows for proper...

  • AR-9 Pistol Buffer Tube Kit - 5.4oz (9mm) Buffer

    AR-9 Pistol Buffer Tube Kit - 5.4oz (9mm) Buffer

    Reduce recoil and dial in your AR-9 build the right way. The 9mm cartridge utilizes blowback functionality to cycle in the AR platform. That means no gas system's required. But that also means the recoil impulse -- and the energy imparted on the bolt...

  • MOE+® AR15/M4 Grip by Magpul® MOE+® AR15/M4 Grip by Magpul® MOE+® AR15/M4 Grip by Magpul®

    MOE+® AR15/M4 Grip by Magpul®

    Magpul® has absolutely built a name for themselves over the years with their aftermarket AR parts and add-ons. Take their MOE® grip for your AR. It feels excellent, the grip angle is lightyears ahead of the standard A2 grip your AR probably came...

  • Lower Parts Kit for .223/5.56 by Spike's Tactical

    Spike's Tactical Lower Parts Kit for .223/5.56

    The mil-spec lower parts kit is adequate. It does the job it was designed for. The trigger, hammer, disconnector, detents, springs, and roll pins are perfectly suited to the job of making your lower (and the rest of your AR) work as intended. As with the...

  • PRS® GEN3 Precision-Adjustable Stock by Magpul

    Magpul® PRS® GEN3 Precision-Adjustable Stock

    The Magpul PRS GEN3 Precision has Melonite coated steel shafts that protects against corrosion and wear, offering the ability to adjust the length of pull and the cheek piece via aluminum detent knobs. This stock includes a non-slip rubber butt-pad that...

  • QMS Quality Mil-Spec Trigger by ALG Defense

    ALG Defense QMS Quality Mil-Spec Trigger

    There are some who prefer their AR platform rifles traditional or built as close to mil-spec as possible. They enjoy replicas of the Colt model 629 or of the old-school M-16, because they want that nostalgia when they shoot. But there's one problem: the...

  • PSA 9MM SBA3 MOE EPT Pistol Lower Assembly Kit

    PSA 9MM SBA3 MOE EPT Pistol Lower Assembly Kit

    Here's the one-stop-shop for building a highly efficient and ergonomic lower for your next AR-9 pistol. This ensemble features parts from some of the best brands out there. First of all, you get the Magpul MOE trigger guard and pistol that will make...

  • NiB-X Lower Parts Kit, Mod 3 by WMD Guns

    WMD Guns NiB-X Lower Parts Kit, Mod 3

    You know, you can get more out of your AR shooting experience even just by making minor changes to your AR's lower parts kit. This lower parts kit by WMD Guns is mil-spec save for one detail: the trigger, hammer, and disconnector have all been coated in...

  • Gauntlet Arms AR-15 Minimalist Stock Gauntlet Arms AR-15 Minimalist Stock 2 Gauntlet Arms AR-15 Minimalist Stock 3

    Gauntlet Arms AR-15 Minimalist Stock

    Lightwest, padded, compatible with mil-spec buffer tubes. Bigger isn't always better. The Gauntlet Arms AR-15 stock provides that compact, "PDW" profile without sacrificing appropriate length of pull, comfort, nor cheek weld. It's a perfect balance of...

  • Bravo Company AR-15 Trigger Assembly - PNT, Nickel

    Bravo Company AR-15 Trigger Assembly - PNT, Nickel

    It's time to get in the game with your AR's trigger. Two words: Bravo Company. And this is their PNT Trigger Assembly. Yeah, it's been given a nickel finish, but it doesn't stop there. The interacting surfaces of its parts have also been coated in...

  • RA-535 Advanced Performance Drop-In Trigger RA-535 Advanced Performance Drop-In Trigger RA-535 Advanced Performance Drop-In Trigger

    RA-535 Advanced Performance Drop-In Trigger

    Your search for the ultimate AR trigger means discovering a quality unit that eliminates the worst traits found on some triggers. You'll want to minimize take-up - that loose, dangly feeling you notice before putting pressure on your trigger...

  • Single Stage Drop-In Trigger Single Stage Drop-In Trigger-2 Single Stage Drop-In Trigger-3 Single Stage Drop-In Trigger-4 Single Stage Drop-In Trigger-5

    Single Stage Drop-In Trigger

    The trigger or "fire control group" as it's officially called, is one of your AR's most basic parts. And sure, there are a ton of flavors out there from who knows how many brands ironically with several takes on what constitutes "mil-spec" that will all...

  • MIAD Mission Adaptable Grip by Magpul MIAD Mission Adaptable Grip by Magpul

    Magpul® Adaptable Grip - MIAD Mission

    Got a preference for the way you think your AR grip should feel? Sure, anything but the original mil-spec grip, right? We hear ya. Fortunately for you, Magpul heard ya too. That's why there's the MIAD, the Mission Adaptable grip for your AR. It's just as...

62 of 62 Items

Finish or upgrade your stripped lower or fabricated 80% lower.

Finished your 80% lower? Grabbed a stripped receiver that you're ready to assemble? We've got you covered with all the AR lower assembly components you need -- or want to upgrade! Check out the mil-spec LPKs we have in stock. They work with all fabricated 80% units and every mil-spec "retail" lower on the market, including the various calibers you might own: 9mm, 5.56, .223, .308, 300 BLK and more.

Quality AR-15 Lower Parts, Triggers, and Kits

The stock AR trigger gets the job done, sure. But you can enjoy better shot placement and a more ergonomic grip with a few easy drop-in upgrades. We've partnered with Rise Armament, JMT, PSA, Hogue, and other top AR parts makers to offer up some of the best upgraded AR triggers and grips available for the AR platform. 

"How do I install my lower parts kit?"

Installing the lower parts kit in your stripped receiver or fabricated 80% lower is relatively easy. Some basic tools are required, which include:

Need help? Here's our detailed lower parts kit install guide!

"What parts do I need to finish my stripped lower?"

You'll need the following parts, which can all be found right on this page or by clicking the links below to filter products by type: 

Not sure what to buy? Here's our complete parts guide to building the AR-15.

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