Description
M4 Lower Rail Handguard Assembly
This M4 lower rail handguard assembly is an original U.S. military replacement lower rail section for M4 / M4A1-style carbine rail systems. The sealed package label identifies the part as Lower Handguard Assembly, with NSN 1005-01-453-1633 and part number 12973099.
M4 Lower Rail Handguard Assembly
This is the lower aluminum handguard rail section, not a standard plastic M4 handguard. The part features black aluminum construction with a 1913 Picatinny rail profile, allowing compatible vertical grips, rail covers, lights, and other accessories to mount to the lower portion of the handguard system.
Construction / Configuration / Pattern
The handguard is sealed in its original blue military protective bag. The label identifies the part with CAGE 04099, P/N 12973099, NSN 1005-01-453-1633, contract number W52H09-07-D-0236 / 0001, M4 1/08, and lot number CAI08A001-002.
The part itself is a black aluminum lower rail handguard assembly with 1913 Picatinny slots and visible mounting holes. This is a replacement lower rail section only, not a complete upper and lower rail handguard set.
Historical Context / Pattern Development
As M4 and M4A1 carbines became increasingly accessory-driven during the GWOT era, aluminum rail handguard systems replaced or supplemented earlier smooth polymer handguards. These rail systems allowed lights, foregrips, lasers, sling mounts, and other mission-specific accessories to be mounted directly to the rifle.
Replacement lower rail handguard assemblies like this were supplied through the U.S. military parts system to maintain M4 rail-equipped carbines in service. The NSN, contract, and part-number markings make this a useful piece for collectors, armorers, and correct military M4 builds.
Condition
New old stock condition in original sealed military packaging. The blue protective bag remains intact with original barcode and identification labels present. The lower rail assembly inside appears unused. Packaging may show light storage wear, wrinkles, label wear, or minor handling marks from surplus storage.
Listing Disclaimer
Listing is for one M4 lower rail handguard assembly only. Buyer is responsible for verifying compatibility with their specific rifle, rail system, or handguard setup.
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