Davidson Defense Nox w/BTR Brace 4.5-inch 1:7 300 BLK AR-15 M-Lok Handguard Pistol Full Build Kit

Nox 4.5-Inch 1:7 .300 BLK AR-15 M-LOK Handguard Pistol Full Build Kit with Magpul BTR Brace

The Nox Full 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, a 4-inch K-style free-float M-LOK handguard, and a complete BCG, charging handle, and Magpul BTR pistol brace. Lower receiver is 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, compatible with 9mm and .350 diameter projectiles, on 5/8x24 threads with 5/8-inch black crush washer
• Complete AR-15 BCG (5.56 NATO, .223 Remington, .300 Blackout, .350 Legend compatible), made in the USA, and mil-spec quality M4-style charging handle included
• Complete mil-spec AR-15 Lower Parts Kit and buffer-system components included
• Magpul BTR pistol brace included
• Lower receiver is 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.

Bolt Carrier Group and Charging Handle

A complete, US-made AR-15 bolt carrier group is included, rated for 5.56 NATO, .223 Remington, .300 Blackout, and .350 Legend, along with a mil-spec quality AR-15 M4-style charging handle.

Lower Parts Kit and Buffer System

The kit includes a complete mil-spec AR-15 Lower Parts Kit with a standard A2-style pistol grip and full fire control group, along with the carbine castle nut and mil-spec receiver end plate. The buffer system pairs a 3-ounce standard AR-15 carbine buffer with a USA-made standard AR-15 carbine recoil spring, cycling inside a heavy-duty mil-spec AR-15 six-position carbine buffer tube.

Brace

A Magpul BTR pistol brace in black is included, compatible with the standard mil-spec AR-15 carbine buffer tube used in this build.

Follow all manufacturer instructions and safe handling practices.

Ensure compliance with all applicable federal, state, and local laws.