The U.S. Defense Department and weapons manufacturer Lockheed Martin finalized a $34 billion contract for the delivery of 478 advanced F-35 fighter jets, the sides announced Tuesday.

It is the largest contract to date for the fifth-generation aircraft, and includes 291 jets for the U.S. military, 127 for the program’s international partners and 60 allocated to foreign military sales.

Read more: Pentagon, Lockheed Martin ink $34B F-35 contract