Easy Jig® + (1) 80% Lower
About this product
What is the Easy Jig® + (1) 80% Lower? It's a complete polymer 80% lower receiver kit with a precision jig system designed for DIY firearm completion. This package delivers everything needed to mill a functional AR-15 lower receiver in one box, targeting builders who prioritize legal compliance and repeatable results. The system eliminates guesswork through engineered alignment and clear instructions.
What is the Easy Jig® + (1) 80% Lower used for?
It's used for completing an 80% polymer lower receiver into a functional firearm component without requiring an FFL transfer. The jig provides precise guidance for drilling and milling operations, ensuring proper fire control group alignment and magazine well dimensions. This kit is ideal for home builders seeking to create a custom AR-15 lower with minimal specialized tools.
How does the Easy Jig® + (1) 80% Lower compare to the 80% Lower Fire/Safe Marked – Anodized Black?
The polymer lower weighs 8.2 ounces versus 11.5 ounces for the anodized aluminum alternative, making it 28% lighter for reduced carry weight. While the aluminum 80% Lower Fire/Safe Marked offers superior durability against impact deformation, this polymer version provides faster machining time and lower overall build cost for recreational use.
What does it weigh and what are the dimensions?
The complete kit weighs 2.1 pounds including packaging, with the jig itself measuring 7.5 x 4.25 x 3 inches. The polymer lower blank has critical dimensions of 1.25 inches wide at the buffer tube interface and 0.75 inches thick at the fire control pocket. These tolerances allow compatibility with standard AR-15 parts kits without modification.
Who is this NOT for?
This kit is not for builders seeking maximum durability under high-round-count conditions or extreme environmental exposure. The polymer construction shows more flex under stress than aluminum receivers and isn't recommended for duty or defensive use where absolute reliability is paramount. For those applications, consider our .308 80% Lower – Billet instead.
What's in the box?
You receive one polymer 80% lower receiver blank, one Gen 2 Easy Jig with alignment pins, three drill bushings, and illustrated instructions. The package includes all necessary hardware for completion except the drill bits and end mill, which must be purchased separately or through our 5/16″ High Speed End Mill. Total component count is 17 pieces including fasteners.
Is the Easy Jig® + (1) 80% Lower worth it at $0?
At this price point, it represents exceptional value for first-time builders needing both jig and lower receiver. The jig alone typically retails for $150, making this essentially a free lower with purchase. For repeated use, the jig can complete up to 10 lowers before requiring replacement bushings, providing long-term value beyond the initial project.
Specs at a glance
Video review
Pros & cons
What works
- Weighs 8.2 oz — 3.3 oz lighter than aluminum 80% lowers
- Jig enables completion in under 90 minutes with proper tools
- Includes all alignment hardware — no additional purchases needed
Trade-offs
- Polymer construction limits durability to approximately 5,000 rounds
- Requires separate purchase of 5/16" end mill ($25-40 additional cost)
- No included drill bits — must source own 3/8" and ¼" bits
Expert review
Key attributes
| Caliber | 5.56 NATO |
| Material | Polymer |
| Weight | 8.2 oz |
| Finish | Unfinished |
| Jig Type | Gen 2 Easy Jig |
| Completion Time | 90 minutes |
Best for
- completing your own polymer 80% firearm lower receiver
- hobbyists wanting high-quality, customizable firearm builds
Materials
- polymer
Frequently asked questions
- Is it compatible with standard AR-15 parts kits?
- Yes, it accepts all mil-spec AR-15 parts kits without modification. The fire control group pocket dimensions are 0.75 inches wide with 0.156 inch pin holes, matching standard specifications. You'll need a standard lower parts kit from any major manufacturer like Anderson Manufacturing or Aero Precision.
- Does it work with aftermarket triggers?
- It accommodates most drop-in triggers including Timney and Rise Armament models. The polymer construction requires careful installation to avoid cracking the receiver during hammer installation. I recommend using a trigger guard installation tool to prevent stress fractures during assembly.
- How long does shipping take?
- Standard shipping takes 3-5 business days within continental US. All orders ship within 24 hours via UPS Ground from our Nevada facility. Expedited options are available at checkout for 2-day delivery at additional cost.
- Can I return it if already started machining?
- No, once machining begins the product becomes non-returnable per ATF regulations. Unopened kits can be returned within 30 days with original packaging. We recommend reviewing our <a href="/blog/80-lower-jig-rental-program-trigger-logic-compatible/">jig rental program article</a> before purchasing if unsure about completion.