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Polymer80 RL556V3 - RHINO 80% AR15 Lower Receiver ONLY

Out of Stock

The most popular polymer AR-15 80% lower.

Aluminum 80% lowers can seem challenging to fabricate. That's why Polymer80 introduced the "RHINO" RL556v3, a hugely popular, easier-to-machine 80% lower for the AR platform.

It's made from a glass-reinforced nylon composite. That's the same material used to make handgun frames. It's incredibly tough and capable of handling centerfire rifle cartridges, but it's a breeze to cut and drill for beginners with basic tools.

The RL556v3 features some improvements over its prior models: A threadless pistol grip reduces stress points within the receiver, and the buffer tube housing has been beefed up. It also features a flared magazine well for quicker reloads.

NOTE: Unlike other Polymer80 lowers and frames, this model does not include an 80% jig or tooling. This lower is compatible with most AR-type 80% jigs. An RL556v3 80% jig is also available.

"RHINO" Polymer 80% Lower: What's Included

  • 80% Polymer AR15 Lower Blank (Mil-spec)
  • Hex Key
  • Set Screw 
  • Grip Nut
  • Grip Screw
  • Bolt Catch Pin

"RHINO" Polymer 80% Lower Features


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

.223 Wylde
Polymer Composite

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, Hawaii, 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.