Starting the week off at a brisk pace, the U.S. Department of Defense awarded a dozen defense contracts Monday, worth a combined $1.375 billion. Just one single company claimed the bulk of the funds: Lockheed Martin (NYSE:LMT).

The contract in question, characterized as a modification to an existing contract, will pay Lockheed Martin $852.3 million to supply special tooling and test equipment that buyers of "Low Rate Initial Production Lot 6" F-35 fighter jets will require after purchasing the aircraft. Buyers of planes included in this LRIP production lot include the U.S. Navy, U.S. Air Force, and international partners the United Kingdom and Italy.

In total, eight countries count as partners to the U.S. in building (and buying) the F-35: Australia, Canada, Denmark, Italy, the Netherlands, Norway, Turkey, and the U.K. The plane is currently in service with the U.S. Air Force, Marine Corps, and Navy, as well as with the militaries of the United Kingdom and the Netherlands.

Monday's contract is expected to be completed in December 2016.