Davidson Defense Atriox w/Magpul BTR Brace 6-inch 1:10 9MM AR-9 M-Lok Handguard Pistol Full Build Kit

Atriox w/Magpul BTR Brace 6-inch 9mm AR-9 Full Build Kit

The Atriox w/Magpul BTR Brace is built around a 6-inch 9mm barrel finished in nitride, paired with a 7075-T6 aluminum upper receiver finished in black anodizing. It pairs a 10-inch free-float M-LOK handguard with a muzzle-mounted fake can at the muzzle. It runs on a direct blowback operating system. A complete 9mm bolt carrier group, Mil-Spec charging handle, complete Lower Parts Kit, carbine buffer-system components, and a Magpul BTR pistol brace round out the rest of the build. The lower receiver is not included, leaving the buyer to select and supply that component separately.

Key Features

• 6-inch 9mm barrel, 1:10 twist, Nitride finish
• Direct blowback operating system
• 7075-T6 aluminum upper receiver, black anodized finish
• 10-inch free-float M-LOK handguard with front and rear QD points
• Muzzle-mounted fake can
• Complete 9mm bolt carrier group with external extractor, Glock and Colt-pattern magazine compatibility
• Magpul BTR pistol brace included
• Complete Mil-Spec Lower Parts Kit and carbine buffer-system components included
• Lower receiver is not included.

Barrel and Muzzle Device

The barrel runs 6 inches long, chambered in 9mm and built from 4150 chrome moly vanadium steel with a nitride finish. It carries a 1:10 twist rate and a 1/2x28 muzzle thread. At the muzzle sits a muzzle-mounted fake can, threaded to match the barrel's 1/2x28 pattern, giving the build a suppressor-style appearance without functioning as one.

Upper Receiver and Handguard

The upper receiver is machined from 7075-T6 aluminum and finished in black anodizing, cut with M4 feed ramps for smooth feeding and fitted with a standard AR-15 forward assist assembly. The ejection port carries a standard .223/5.56 door with its rod and spring installed. Over the barrel sits a 10-inch free-float M-LOK handguard finished in black, featuring a quad-rail front section, front and rear QD points, a slanted front, and anti-rotation tabs along its length.

Bolt Carrier Group and Charging Handle

The bolt carrier group is a complete 9mm unit machined from 8620 alloy steel with a nitride finish, fitted with an external extractor for reliable case ejection. It's built for Glock and Colt-pattern magazine compatibility, giving the buyer flexibility depending on the lower this build eventually pairs with. A Mil-Spec AR-15 M4 charging handle rounds out the upper's operating components.

Lower Parts Kit and Buffer System

A complete Mil-Spec AR-15 Lower Parts Kit covers the fire-control and lower-control internals needed once a lower receiver is on hand. Behind it sits a Mil-Spec heavy-duty six-position buffer tube, holding an AR-15 9mm carbine buffer and a standard USA-made recoil spring. A standard castle nut and Mil-Spec AR-15/M16 receiver end plate secure the buffer tube assembly to the lower.

Stabilizing Brace

Capping off the rear of the build is a Magpul BTR pistol brace finished in black. It's built for a standard Mil-Spec carbine buffer tube, matching the buffer tube included with this kit.

Follow all manufacturer instructions and safe handling practices.

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

Lower receiver is not included.