AR15 Lower Parts Kit

AR15 Lower Parts Kit Overview

The AR15 Lower Parts Kit includes everything you need to complete a stripped lower receiver. This is a full mil-spec LPK with quality components throughout, not a bag of mystery parts from overseas. The trigger group is mil-spec, the springs are black oxide coated for corrosion resistance, and every piece is made in the USA.

One thing that sets this kit apart is the included billet trigger guard. Most lower parts kits ship with a stamped aluminum guard that requires a roll pin and careful installation to avoid cracking your lower. The billet guard in this kit is stronger, looks better, and installs easier. It’s a small upgrade that makes a real difference during assembly.

What’s Included in This AR15 LPK

Fire Control Group
Mil-spec hammer, trigger, and disconnector with all associated springs and pins. The trigger and hammer have polished sear surfaces for a clean break. Standard mil-spec pull weight around 6-7 lbs. These parts are investment cast, not MIM, so you don’t have to worry about a cheap hammer breaking on you.

Safety Selector
Standard 90-degree throw selector with detent and spring. Crisp, positive engagement in both safe and fire positions.

Bolt Catch Assembly
Bolt catch, plunger, spring, and roll pin. Proper engagement with the bolt carrier and magazine follower for reliable last-round hold-open.

Magazine Release
Magazine catch, button, and spring. Standard AR15 pattern compatible with all mil-spec magazines.

Pivot and Takedown Pins
Both pins with their detents and springs. These connect your upper and lower receivers and allow field stripping.

Buffer Retainer
Buffer retainer and spring. Keeps the buffer in place when you separate the upper and lower.

Billet Trigger Guard
Machined aluminum trigger guard, not stamped. Stronger than standard guards and easier to install. No roll pin required on most designs.

A2 Pistol Grip
Standard A2 grip with screw and lock washer. The classic grip that works. Swap it out later if you want something different, but this gets you shooting.

Black Oxide Springs
All springs in this kit are black oxide coated. This finish resists corrosion better than bare steel and looks cleaner than the shiny springs in cheaper kits.

What You Still Need

Stripped Lower Receiver
This kit completes a stripped lower. You need the receiver itself, whether that’s a standard forged lower, billet lower, or 80% build you’ve finished yourself.

Buffer Tube Assembly
The LPK does not include the buffer tube, buffer, buffer spring, castle nut, or end plate. You’ll need a complete buffer kit or stock assembly to finish the lower.

Stock or Brace
For a rifle build, you need a stock. For a pistol build, a brace or bare buffer tube. This depends on your barrel length and intended configuration.

AR15 Lower Parts Kit FAQ