TX Arms AR15 Lower Parts Kit

Description

TX Arms AR15 Lower Parts Kit

A well-organized AR15 lower parts kit turns a stripped receiver into a real build, not a pile of loose hardware. TX Arms assembles this kit front to back — specifically, in the order you’ll use each part. That way, you never open bags just to find one roll pin while parts scatter. TX Arms groups the mag catch, bolt catch assembly, pins, and detents by build step rather than by part type. That grouping keeps the kit intact as you work, which means it won’t scatter across the bench.

This AR15 lower parts kit covers the small hardware most builds run short on. In particular, that includes a phosphate-coated magazine catch assembly, a complete bolt catch, and nitrided takedown and pivot pins. On top of that, you get their detents and springs, plus a spare. A buffer retainer pin and spring round out the hardware, alongside your choice of Mil-Spec or ambidextrous safety selector. Because this kit covers fundamentals, not a full trigger group, you’ll need a few more pieces to finish the lower. TX Arms sells the buffer tube kit, grip, trigger guard, and fire control group separately for that reason.

Key Features — AR15 Lower Parts Kit

• Phosphate-coated magazine catch assembly for reliable engagement and a mar-resistant finish
• Bolt catch, detent, spring, and roll pin — plus a toothpick to hold it together while you drive the pin
• Nitrided takedown and pivot pins that press and rotate smoother than a standard finish
• Takedown and pivot pin detents and springs, plus one spare so a dropped part doesn’t stall the build
• Buffer retainer pin and spring
• Mil-Spec or ambidextrous safety selector, selectable at checkout, each paired with its own detent and spring
• Ambidextrous selector variant includes a Vibra-Tite VC-3 threadlocker packet to keep the second selector arm secure

 

Why This Product Stands Out

TX Arms bags this kit the way its own team builds rifles, not the way a distributor palletizes hardware. Bagging by build step, not part number, means you open one bag, finish a step, then move to the next. That pays off once you’re deep into a Saturday build and don’t want to hunt for a stray roll pin. That same attention shows up in the nitrided pins, which resist galling and keep pressing smoothly even after repeated field-stripping.

Notably, the ambidextrous selector option matters most for shooters who train weak-side manipulation or run the rifle left-handed. The included Vibra-Tite keeps that second lever from backing out under recoil, a detail plenty of budget kits skip entirely. Whether you’re finishing a first build or restocking spares, this kit supplies the parts that actually fail or wander off. Not filler you’ll never touch.

Ideal Use Cases

• New AR15 build from a stripped Mil-Spec lower receiver
• Restocking detents, springs, and pins during routine maintenance
• Upgrading from a Mil-Spec to an ambidextrous safety selector
• Armorer and gunsmith bench stock for repairs

 

Technical Specifications

 

Compatibility Information

This AR15 lower parts kit fits standard Mil-Spec AR15 lower receivers. TX Arms sizes every pin, detent, and catch to Mil-Spec dimensions, not a proprietary spec. Billet or non-Mil-Spec lowers may not accept every part — confirm your receiver’s spec before ordering if unsure.

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Manufacturer: TX Arms | Category: AR15 Lower Parts Kit | Compatible Platform: Mil-Spec AR15