Premium 80% Lower Fire/Safe Marked – Billet
Specs at a glance
About this product
Polymer80Deals Premium Billet 80% Lower Receiver – Fire/Safe Marked
This isn’t just another 80% lower. This is our shop-favorite billet model, machined for builders who hate fighting roll pins and want a clean, professional result. We fixed the annoying parts so you can focus on the build.
The main upgrade is simple: threaded holes where you need them. The bolt catch pin and the rear takedown pin detent get installed with screws, not roll pins. No more hammering, no more launching that tiny detent spring across the room. It’s a smarter way to build, saving you time, tools, and frustration. All necessary screws are included in the box.
Machined from a solid block of 6061-T6 aluminum, this lower is tough. It gets a proper Mil-Spec Type III hardcoat anodized finish in matte black for durability that lasts. The magwell is professionally broached for smooth magazine changes, and the trigger guard is machined as part of the receiver itself—no flex, no weak points.
It’s marked “Fire” and “Safe” on the selector, ready for your engraving. This lower is 100% made in the USA and is compatible with standard AR-15 components in 5.56/.223, 300 Blackout, and 6.5 Grendel.
Why This is Our Go-To Billet Lower:
- No Roll Pins: Threaded bolt catch and rear takedown detent holes. Install with an Allen wrench.
- Pro Build, Less Hassle: Designed for a smoother, faster assembly process with fewer specialized tools.
- Billet Tough: CNC-machined from 6061-T6 aluminum billet for strength and precise fit.
- Clean Look: Integrated heavy-duty trigger guard and broached magwell for a seamless, professional finish.
- Ready for Your Mark: Fire/Safe markings are already engraved, waiting for your final machining and serialization.
Specifications:
| Compatibility | Multi-Caliber (5.56/.223, 300 BLK, 6.5 Grendel) |
|---|---|
| Material | 6061-T6 Aluminum Billet |
| Finish | Type III Hardcoat Anodized, Matte Black |
| Fitment | 100% Mil-Spec |
| Fire/Safe Markings | Yes, Engraved |
| Origin | Made in the USA |
Price: $77.00
For a billet 80% lower that makes the assembly process straightforward and the final product rock-solid, this is the one. Grab yours at Polymer80Deals and build it right.
What's in the box
- Premium 80% Lower Fire/Safe Marked – Billet