80% Lowers Fire/Safe (1-pack) & Polymer80 RJ556U - Universal 80 Lower Jig (With Tooling)

(You save $20.00 )


A lot of shooters invest in 80% lowers because building your AR-15 from scratch can ultimately save you money -- if you buy the right stuff. That means picking the right jig, bits, and 80% lower receiver itself. We made it simple and created a combo kit that pairs arguably the most affordable jig on the market with the most popular, proven, and affordable mil-spec lower receiver.

Includes Forged 80% Lower
The O.G. forged 80% lower is what made this entire hobby famous. It’s been trusted by hundreds of shooters and AR owners and comes with a quality Type III Hardcoat anodized finish. It’s also engraved with “FIRE” and “SAFE” markings. All other components are fabricated besides the pinholes and fire control cavity, making machining quick and easy.

Lower Receiver Specs

  • Type III Hard Anodized
  • 100% Mil-Spec Fittings
  • Fire/Safe Marked: Yes
  • Forged 7075 Aluminum
  • Broached Magazine Well
  • Made in the USA
  • Not considered a firearm

The Polymer RJ556U Jig
Unlike many other 80% jigs, the RJ556U Jig truly only needs you to have a drill press. No router or milling machine is required, saving you even more money. With a basic press and vise, you can complete your receiver and make it ready for a lower parts kit install in less than one hour.

What’s Included

  • (1) Forged 80% Lower
  • (1) 80% Finishing Jig
  • (1) Set of drill bits
  • (1) Set of end mill bits
  • Written instructions

Ready to get building? Download detailed instructions here.

No FFL required  Made in the USA  Lifetime Warranty

Shipping Restrictions

Shipping of various parts and/or accessories are prohibited to states and locales (ie New Jersey, California, New York, etc…) with restrictions against certain parts and/or accessories or “assault weapons” (i.e. states with high-capacity magazine restrictions, manufacturing of semi-automatic weapons, etc..). It is your responsibility to be aware of your local firearms laws before purchasing from our website or machining a firearm. We try our best to keep our shipping page current, but laws change daily

80-Lower.com only ships within the United States. Federal legislation dictates we cannot ship our products internationally.

We are a national retailer of individual components and not all products depicted on this website are legal in every state. Shipping of various products found on this website are prohibited to some states (such as California, Connecticut, District of Columbia, New Jersey, New York, Rhode Island, and Washington). The information, pictures, text or products presented on this website are not a representation by us, and should not be understood by you, that any product or completed firearm is legal to assemble or own in your state of residence. We encourage each and every builder to perform their own research about the state and federal laws that apply to them. It is your responsibility to understand the law and we encourage you to consult with an attorney or your local ATF representative.