The U.S. defense giant Lockheed Martin has received a $2.43 billion modification to its contract for the Lightning II Joint Strike Fighter program.

The modification to the firm-fixed-price Naval Air Systems Command contract involves initial spares for the Marine Corps, Navy, Air Force, non-U.S. Department of Defense (DoD) participants, and Foreign Military Sales (FMS) customers.

“Spares to be procured include global spares packages, base spares packages, deployment spares packages, afloat spares packages and associated consumables,” the Department of Defense said in the statement.

According to the current information, all orders are expected to be placed no later than December 2020.

The F-35 Lightning is a supersonic, multi-role fighter jet that represents a quantum leap in air-dominance capability, offering enhanced lethality and survivability in hostile, anti-access airspace environments.

The U.S Department of Defense is developing and fielding a family of fifth-generation strike fighter aircraft integrating stealth technologies with advanced sensors and computer networking capabilities for the United States Air Force, Marine Corps, and Navy, eight international partners, and four foreign military sales customers. The family is comprised of three aircraft variants.

The Air Force’s F-35A variant will complement its F-22A fleet and is expected to replace the air-to-ground attack capabilities of the F-16 and A-10. The Marine Corps’ F-35B variant will replace its F/A-18 and AV-8B aircraft. The Navy’s F-35C variant will complement its F/A-18E/F aircraft.