The U.S. Navy is buying another 285 SM-2 anti-aircraft missiles, at a cost of about half a million dollars each. Spare parts and accessories are being purchased as well. Many of these will go to foreign users (Japan, the Netherlands, Germany, Taiwan, Canada, and Korea) of the SM-2 naval anti-aircraft missile. While hardly any of these missiles have been used in wartime, each ship fires some of them periodically to make sure the system works. Last years order for SM-2s was only 163. The SM-2 is the principal anti-aircraft missile for the US Navy, and many American allies.