The Kilos weigh 2,300 tons (surface displacement), have six torpedo tubes, and a crew of 57. They are quiet and can travel about 700 kilometers under water at a quiet speed of about five kilometers an hour. Kilos carry 18 torpedoes or SSN-27 anti-ship missiles (with a range of 300 kilometers and launched underwater from the torpedo tubes). The combination of quietness and cruise missiles makes Kilo very dangerous to surface ships. The new Iranian components have probably made these boats louder and easier to find. U.S. and allied anti-submarine forces will be keen to play with the refurbished Kilo when it ventures out into international waters (which it may avoid doing to prevent anyone from "hearing" how this Kilo has changed).