On Wednesday, Navistar (NYSE:NAV) announced that its defense unit has been tapped to fulfill an "urgent delivery order" from the U.S. Army's TACOM LCMC department, retrofitting 205 Navistar Medium Tactical Vehicles, or MTVs, with armored cabs for use by the Afghan National Security Forces.

The vehicles, currently equipped with standard commercial-quality cabs, require upgrading with armored cabs to protect "from ballistic and blast threats in the theater of operations" -- said theater being pretty much the entire country of Afghanistan. Additional upgrades are also being requested as part of the $23 million task order, with the aim of making the MTVs usable for route clearance and mine roller operations. Work on the contract is expected to begin in April and to conclude by July.

The standard version of the MTV is not ordinarily an armored vehicle, being more commonly configured to serve such functions as general troop transport, fuel and water tanker truck delivery, and cargo shipment. Navistar has already built and delivered nearly 9,000 ordinary MTVs to the Afghan National Army and Afghan National Police.

Navistar shares closed down 4.9% in Wednesday trading, closing at $25.91.

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