A multi-year bulk buy contract has been awarded to Raytheon to provide Japan with upgrade kits and other equipment for the Phalanx Close-In Weapons System.

Phalanx is used on Japan Maritime Self-Defense Force ships and a is critical defense capability against threats that have penetrated outer defense systems.

"Phalanx provides the critical inner-layer of protection to sailors around the globe against threats that are continually evolving," said Rick Nelson, vice president of Raytheon Missile Systems' Naval and Area Mission Defense product line. "Thanks to its array of sensors, Phalanx brings a proven solution against threats launched from land, sea or air."

The Phalanx was brought into service with the U.S. Navy in 1980. The system consists of a rapid-fire, six-barrel 20 mm gun with a computer radar control for acquiring and tracking threats.

The gun can fire at a rate of 4,500 rounds a minute. Effective range is about two miles.

Additional equipment to be supplied to Japan under the contract, which is worth more than $200 million, include support equipment and hardware spares, Raytheon said.

Raytheon made the contract announcement at the Euronaval 2014 exhibition in France.