Maxim Defense PDX Complete Upper – 5.56 NATO/.223, 5.5” Barrel, ARID (FDE) Finish, AR-15 Compatible, PDW Compact Upper Receiver

The CQB elite tier with the Maxim Defense PDX Complete Upper — one of the most compact, rugged, and reliable setups in the ultra-short-barrel game. With its 5.5” barrel, ARID (Flat Dark Earth) finish, and battle-proven PDW performance, this upper is purpose-built for those who need maximum firepower in minimal space.

Engineered for the demands of close-quarters combat and high-threat environments, the Maxim Defense PDX Complete Upper delivers unmatched power in an ultra-compact form. Chambered in 5.56 NATO/.223 Remington, this upper features a 5.5” barrel, optimized for maximum maneuverability and control without sacrificing reliability.

Finished in Maxim’s signature ARID Flat Dark Earth Cerakote, the PDX upper doesn’t just perform — it dominates with style. Featuring the proprietary Maxim HATEBRAKE muzzle booster, it reduces concussion and redirects blast forward, making it ideal for confined spaces or team-based operations.

⚙️ Key Features:

• Caliber: 5.56 NATO / .223 Rem

• Barrel Length: 5.5″

• Barrel Material: Cold Hammer Forged

• Muzzle Device: Maxim HATEBRAKE™ – Blast redirector for CQB use

• Gas System: Direct Impingement – Optimized for SBR & PDW builds

• Upper Receiver: Monolithic-style, billet aluminum construction

• Finish: ARID (Flat Dark Earth) Cerakote – Rugged and durable

• Handguard: Integrated M1913 Picatinny rail + M-LOK mounting slots

• Includes: Complete upper assembly with barrel, gas system, and muzzle device

• Excludes: BCG and charging handle

• Platform Compatibility: AR-15

• Made in the USA

Whether you’re building a personal defense weapon (PDW), a truck gun, or just a bad-ass CQB rig, the PDX upper delivers serious firepower and unmatched control in the tightest packages.

FAQ:

Q: Is the BCG and charging handle included?
A: No — the PDX upper ships without a BCG or charging handle, allowing you to choose your preferred components.

Q: Can I run this upper on a standard AR-15 lower?
A: Yes — it fits any mil-spec AR-15 lower, but it’s best paired with an SBR or pistol lower (ensure compliance with NFA rules).

Q: What’s the HATEBRAKE muzzle device?
A: Maxim’s proprietary HATEBRAKE redirects blast forward, reducing felt concussion — perfect for CQB and indoor use.

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