Davidson Defense Nox 4.5-inch 1:7 300 BLK AR-15 M-Lok Handguard Pistol Upper Build Kit

Nox 4.5-Inch 1:7 .300 BLK AR-15 M-LOK Handguard Pistol Upper Build Kit

The Nox Upper Build Kit is built around a 4.5-inch .300 AAC Blackout Bear Creek Arsenal HBAR barrel with a micro-length gas system, a 7000 Series optimized upper receiver, and a 4-inch K-style free-float M-LOK handguard. BCG and charging handle are not included.

Key Features

• 4.5-inch Bear Creek Arsenal HBAR barrel, .300 AAC Blackout, 4150 CMV steel, 1:7 twist, Parkerized finish
• Micro-length gas system, 5.25" gas tube
• 7000 Series optimized upper receiver, Type III hardcoat anodized black, integrated dust cover pin feature
• 4-inch K-style ultra-lightweight minimalist M-LOK handguard
• Steel flash can, Design 4, Black Oxide finish, 9mm and .350 diameter compatible, on 5/8x24 threads with 5/8-inch black crush washer
• BCG and charging handle are not included.

Barrel and Gas System

The 4.5-inch Bear Creek Arsenal barrel is built in an HBAR heavy profile from 4150 chrome moly vanadium steel with a Parkerized finish and a 1:7 twist rate suited to .300 AAC Blackout. It runs a micro-length gas system through a 5.25-inch gas tube and a micro low-profile steel gas block with a .750-inch diameter, matched to the barrel's .750-inch gas journal. At the muzzle, 5/8x24 threads carry the included steel flash can, Design 4, finished in Black Oxide and compatible with 9mm and .350 diameter projectiles, secured with the supplied 5/8-inch black crush washer.

Upper Receiver and Handguard

The upper receiver is a 7000 Series optimized unit finished in Type III hardcoat black anodizing with an integrated dust cover pin feature, and it includes the ejection port door, rod, and spring. It's paired with a 4-inch K-style, ultra-lightweight minimalist free-float M-LOK handguard, built without anti-rotation tabs for a slim profile along the short barrel.

Follow all manufacturer instructions and safe handling practices.

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