AR-15 M-LOK Rail Build Kit with USB

AR-15 M-LOK Rail Build Kit Legal and Safety Information

The AR-15 M-LOK Rail Build Kit is a firearm-component package described as including a 16-inch upper assembly, lower-receiver components, and a USB device containing digital material. This section provides general legal, compatibility, and safety information only.

It does not contain technical files, 3D-printing parameters, machining dimensions, assembly procedures, or firearm-manufacturing instructions.

Verify the Physical Contents

The listed configuration includes a 16-inch, 5.56 NATO upper with a mid-length gas system and a 13.5-inch M-LOK handguard. A bolt-carrier group, charging handle, flip-up sights, lower-parts components, and buffer-related components may also be included.

Customers should review the current itemized package contents rather than assuming that every component required for a complete firearm is present. The listing states that a finished lower receiver is not included.

Digital Materials on the USB

The USB supplied with the AR-15 M-LOK Rail Build Kit is described as containing a digital receiver design file. The presence of this file does not establish that downloading, possessing, distributing, printing, or using it is lawful in every jurisdiction.

Digital materials should be protected against unauthorized access and evaluated for malware or other cybersecurity risks before opening. This content does not validate or reproduce the supplied files.

Legal Classification

Federal regulations address partially completed receivers and certain component packages that may be readily converted into functional firearms. Legal classification can depend on the kit’s exact contents, level of completion, included tools or instructions, and surrounding circumstances.

State and local laws may separately regulate privately made firearms, unfinished receivers, 3D-printed components, serialization, registration, background checks, digital firearm files, magazine capacity, and component possession.

Before acquiring, transferring, printing, modifying, or using the AR-15 M-LOK Rail Build Kit, customers should consult the relevant authorities or a qualified firearms attorney.

Compatibility and Professional Inspection

Component compatibility should be verified based on caliber, receiver pattern, gas-system length, buffer system, bolt-carrier group, barrel extension, and fire-control components. Similar-looking AR parts are not always safely interchangeable.

Any lawfully completed firearm should be inspected by a qualified gunsmith before loading or operation. Incorrect dimensions, unsuitable printed materials, or incompatible components may cause structural failure, serious injury, or death.

Listed Upper Specifications

• Caliber: 5.56 NATO
• Barrel length: 16 inches
• Twist rate: 1:7
• Gas system: Mid-length
• Barrel material: 4150 chrome-moly vanadium
• Barrel finish: Nitride
• Handguard: 13.5-inch M-LOK
• Receiver material: Forged 7075-T6 aluminum
• Bolt-carrier group: Listed as included
• Charging handle: Listed as included