Polymer80Hub Exclusive: Billet AR-9 80% Lower Receiver – Fire/Safe Marked

Our Price: $93.49

Built here. Finished by you. A solid foundation for your 9mm build.

This isn’t a flimsy starter part. This is a serious, machined-from-solid-billet 6061-T6 aluminum AR-9 lower receiver. We start with a block of aircraft-grade aluminum and our CNC machines cut it to exacting specs. The result is a receiver that’s rigid, durable, and has a clean, professional look right out of the box.

It’s finished in a proper Type III Hardcoat Anodizing. This isn’t just for color; it’s a hardened surface layer that resists wear, scratches, and corrosion. This lower is built to be handled and used.

Designed for Function, Not Just Looks

• Glock Magazine Ready: Designed from the ground up for reliable feeding with Glock OEM and ETS magazines. No adapters, no fuss.
• Flared Magwell: We machined in an enlarged, flared magwell. This gives you a real, tactile advantage for faster, more positive reloads, especially under pressure.
• Fire/Safe Marked: The selector markings are professionally engraved. Once your build is complete, it has the correct, finished markings.
• 100% Mil-Spec Fitment: This lower mates with standard AR-15 upper receivers and parts kits. You won’t be hunting for proprietary parts.
• One-Piece Design: The trigger guard is integrated into the receiver. It’s not an add-on. It’s stronger and cleaner.

Important Note: This is an 80% lower receiver. It requires machining to complete. You are responsible for following all federal, state, and local laws regarding the manufacture and possession of firearms. This is for experienced builders who understand the process and legal requirements.

If you’re building a 9mm AR pistol or carbine and want a lower that’s tougher than a standard forged part, this billet model is the way to go. It’s 100% made in the USA, built with precision, and priced right for a serious builder.

Get the foundation for your best 9mm build. Add the Polymer80Hub Billet AR-9 80% Lower to your cart today.