CA is also the hull classification symbol for heavy cruiser, derived from the old name for such vessels - Cruiser, Armored. After World War II, when ships armed with guided missiles became the norm, all cruisers armed only with guns, whether 155mm or 203mm (or larger), were redesignated as CAs. No ships of this type remain in service as of 2006, except for the Peruvian Almirante Grau (which isn't strictly a gun cruiser since it has OTOMAT surface-to-surface missiles, in addition to its eight 152mm cannon).