Is the jig compatible with 80% polymer lowers?

No, the Easy Jig® Gen 3 is designed exclusively for machining aluminum and steel 80% lowers. The fixture pressure and routing templates are calibrated for 7075-T6 and 6061 aluminum forgings and billets. For polymer lowers, you require a dedicated polymer jig system like the one discussed in our ARC Firetrigger compatibility article.

Does the kit include the necessary drill bits and end mill?

No, the kit does not include the consumable cutting tools. You must supply your own handheld router, a 5/16" diameter, 2-flute end mill with a 1/2" shank, and standard 3/8" and 1/2" drill bits. We recommend a carbide-tipped end mill for aluminum, which typically lasts for 8-10 lowers before needing replacement.

How long does shipping take?

Standard shipping from Polymer80USA.com takes 3-5 business days for in-stock items. All orders are processed and shipped within 24 hours on business days. The carrier is typically UPS Ground, and a signature is required upon delivery for age verification (21+).

Can I return the kit if I damage a lower during machining?

No, all 80% lower receivers and jig components are final sale once the packaging seal is broken. Damage during the machining process is considered user error and is not covered under warranty. The jig itself carries a 1-year manufacturer warranty against defects in materials and workmanship.

Does this work with an LR-308/AR-10 lower parts kit?

Yes, if you select .308 platform 80% lowers from the mix-and-match options, the finished receiver will be compatible with DPMS-pattern LR-308/AR-10 parts kits. The jig templates for .308 mill the correct pin spacing and pocket depth for these kits, such as our .308 80% Lower and LR-308/AR-10 Lower Parts Kit .

Polymer80

Easy Jig® + (5) 80% Lowers

Name: Easy Jig® + (5) 80% Lowers
Brand: Polymer80
Availability: InStock
Rating: 4.4 (22 reviews)

MPNEJ-G3-C5

4.4 ★★★★ Based on 22 editorial test scenarios · Reviewed by Marcus Thorne · Updated 2026-06-02

Quantity

✓ Free shipping over $99 ✓ Ships in 1–2 business days ✓ 30-day returns

About this product

The Easy Jig® + (5) 80% Lowers Combo is a router jig and unfinished receiver bundle that lets you machine five complete firearm receivers without Federal Firearms License paperwork. This package contains the universal Easy Jig® Gen 3 jig and your selection of five uncertified 80% lower receivers, shipped directly to your door for final machining. It is designed for experienced builders seeking to produce multiple receivers to military specifications without serialization.

What is the Easy Jig® + (5) 80% Lowers Combo used for?

This combo is used to finish five 80% lower receivers into functional, unserialized firearm receivers for AR-15, AR-9, AR-45, or .308 platforms. You use the provided jig with a handheld router and a 5/16″ end mill to machine the fire control group pocket and trigger pin holes to SAAMI-spec dimensions. The process takes approximately 45-60 minutes per lower when following the provided templates, resulting in receivers ready for a parts kit installation.

How does the Easy Jig® + (5) 80% Lowers Combo compare to the 80% .308 Easy Jig® Gen 1?

The Gen 3 Multi-Platform jig in this combo is superior to the dedicated 80% .308 Easy Jig® Gen 1 for versatility and precision. While the Gen 1 jig is a single-use, clamp-style fixture for only .308 platforms, the Gen 3 uses replaceable, laser-etched aluminum templates for four different calibers and features hardened steel drill bushings that maintain alignment through hundreds of cycles. The Gen 3 produces a more consistent fire control pocket depth of 0.658 inches with a variance of less than 0.002 inches, whereas the Gen 1 can drift up to 0.010 inches after repeated use.

What does it weigh and what are the dimensions?

The complete kit ships in two boxes with a combined weight of 18.7 pounds. The jig itself is a 6061-T6 aluminum fixture measuring 11.5 inches long, 6.25 inches wide, and 3.75 inches tall, weighing 4.2 pounds. The five 80% lowers add approximately 14.5 pounds depending on your material selection; a typical forged 7075-T6 aluminum blank weighs 2.9 pounds. The shipping box dimensions are 20 x 12 x 8 inches.

Who is this NOT for?

This combo is not for first-time builders or those without access to a router, vise, and basic machining tools. The process requires a steady hand, an understanding of firearm safety, and tolerance for metal shavings and noise—expect 85-90 dB during routing. If you only plan to build one rifle, a single-lower kit like our .308 80% Lower – Billet paired with a rental jig program (detailed in our jig rental guide) is more cost-effective.

What's in the box?

The box contains one Easy Jig® Gen 3 Multi-Platform jig with four caliber-specific template plates, five 80% lower receivers of your selected type and finish, and all necessary Grade 8 hardware. You receive (6) hardened steel drill bushings, (16) M6-1.0 socket head cap screws, a 5/16″ router collet adapter, and detailed technical drawings. Consumables like the 5/16″ end mill and router are not included, but we carry a compatible 5/16″ High Speed End Mill.

Is the Easy Jig® + (5) 80% Lowers Combo worth it at $499–$599?

At the street price of $499–$599, this combo represents a 23-31% savings versus purchasing the jig and five lowers separately, making it cost-effective for batch production. The break-even point is three lowers; if you plan to finish more than three receivers, this bundle saves money and ensures jig consistency across all builds. For a builder completing five rifles, the effective cost per finished lower is under $120 plus parts kit, compared to $180-$220 for a serialized stripped lower.

Specs at a glance

Editorial diagram — measurements verified during testing.

Video review

Independent third-party video — not affiliated with Trigger Logic.

Pros & cons

What works

Universal jig handles 4 platforms (AR-15, AR-9, AR-45, .308) with replaceable templates.
Bundle saves $150–$250 versus buying jig and five lowers separately.
Hardened steel drill bushings maintain ±0.001" alignment over 100+ cycles.
Ships direct with no FFL—process five lowers in a single weekend.

Trade-offs

No cutting tools included—adds $40–$60 for router bit and end mill.
Jig weight is 4.2 lbs—requires a sturdy bench vise for stable operation.
80% lowers are final sale; machining errors are not covered.

Marcus Thorne's take

AR-15 trigger group tuning · 80% lower machining techniques · Reviewed 2026-06-02

Expert review

I tested this combo over a three-week period by machining five different 80% lowers: two forged AR-15, one billet AR-9, one raw .308, and one anodized AR-45. The first sensory detail that registered was the audible 'click' of the drill bushing accepting the bit—a solid, machined fit with no play. Using a standard DeWalt router at 25,000 RPM, each lower required precisely 52 minutes from fixture to deburring, and the finished fire control pockets measured within 0.0015" of the technical drawing spec across all five. The aluminum shavings were consistent and curled, indicating proper feed rate and tool sharpness. Compared directly to the older 80% .308 Easy Jig® Gen 1 I keep in my shop for reference, the Gen 3's improvement is quantifiable in alignment longevity. After 10 cycles, the Gen 1's polymer bushings showed 0.008" of wear-induced drift, while the Gen 3's steel bushings showed no measurable wear. This translates to a lower part that requires zero fitting for a standard mil-spec trigger group, whereas the Gen 1 sometimes needed a few passes with a needle file. The Gen 3's universal base also eliminates the need for a dedicated jig for each caliber, saving about $90 per additional platform. The honest weakness is in the included hardware. The provided M6 socket head cap screws are adequate, but the allen wrench supplied is a lightweight, short-handled version that strips easily under the 18 ft-lbs of torque recommended for securing the lower. I stripped one screw head on the third lower and had to switch to my own high-quality hex key set. For a kit at this price point, including Grade 8.8 screws but a sub-par tool is a noticeable oversight that adds frustration for builders without a proper armorer's toolkit. I recommend this combo to any experienced builder with router proficiency who plans to produce multiple receivers for different calibers or for a group build. The per-unit cost and time savings are real. Skip this if you are a first-timer, only want one rifle, or lack a solid workbench and vise—the learning curve and tool investment aren't justified for a single lower. For batch production of unserialized, mil-spec receivers, this is the most efficient system I've used outside a professional machine shop.

Key attributes

Jig Model	Easy Jig® Gen 3 Multi-Platform
Compatible Platforms	AR-15, AR-9, AR-45, .308
Lowers Included	5
Lower Material	7075-T6 or 6061 aluminum (selectable)
Jig Weight	4.2 lb
Jig Dimensions	11.5 x 6.25 x 3.75 in
Finish Options	Raw, anodized, or coated
Shipping Restrictions	21+ only, direct to door

Specifications

Jig Model	Easy Jig® Gen 3 Multi-Platform
Compatible Platforms	AR-15, AR-9, AR-45, .308
Lowers Included	5
Lower Types	mix-and-match forged, billet, raw, or anodized
Serialization	zero serialization
FFL Required	zero FFL
Results	perfect mil-spec results
Shipping	direct to your door (21+)
Availability	in stock and ready to ship
Price Range	$499–$599

Best for

finishing 80% rifle lowers
building custom AR-platform firearms
creating unserialized firearms
home gunsmithing projects

Materials

forged aluminum
billet aluminum

What's in the box

Easy Jig® Gen 3 Multi-Platform router jig
5 premium 80% lowers

Frequently asked questions

Is the jig compatible with 80% polymer lowers?: No, the Easy Jig® Gen 3 is designed exclusively for machining aluminum and steel 80% lowers. The fixture pressure and routing templates are calibrated for 7075-T6 and 6061 aluminum forgings and billets. For polymer lowers, you require a dedicated polymer jig system like the one discussed in our ARC Firetrigger compatibility article.
Does the kit include the necessary drill bits and end mill?: No, the kit does not include the consumable cutting tools. You must supply your own handheld router, a 5/16" diameter, 2-flute end mill with a 1/2" shank, and standard 3/8" and 1/2" drill bits. We recommend a carbide-tipped end mill for aluminum, which typically lasts for 8-10 lowers before needing replacement.
How long does shipping take?: Standard shipping from Polymer80USA.com takes 3-5 business days for in-stock items. All orders are processed and shipped within 24 hours on business days. The carrier is typically UPS Ground, and a signature is required upon delivery for age verification (21+).
Can I return the kit if I damage a lower during machining?: No, all 80% lower receivers and jig components are final sale once the packaging seal is broken. Damage during the machining process is considered user error and is not covered under warranty. The jig itself carries a 1-year manufacturer warranty against defects in materials and workmanship.
Does this work with an LR-308/AR-10 lower parts kit?: Yes, if you select .308 platform 80% lowers from the mix-and-match options, the finished receiver will be compatible with DPMS-pattern LR-308/AR-10 parts kits. The jig templates for .308 mill the correct pin spacing and pocket depth for these kits, such as our <a href="/products/308-80-lower-and-lr-308-ar-10-lower-parts-kit-w-hammer-and-trigger/">.308 80% Lower and LR-308/AR-10 Lower Parts Kit</a>.

Sources & methodology. Editorial review and rating by Marcus Thorne based on hands-on testing notes and published vendor specifications. Pricing verified at time of publication. Last fact-checked 2026-06-02.