Specifications 40Rate of fire (round/min) Used by 1972 Iroquois class destroyer DD 11972 Audace class guided-missile destroyer DDG 11982 Maestrale class frigate FF 11983 MEKO 360H2 class destroyer DD 11993 Kongo class guided-missile destroyer DDG 11993 Durand de la Penne class guided-missile destroyer DDG 12002 De Zeven Provinciƫn class guided-missile destroyer DDG 12003 Takanami class destroyer DD 12021 Thaon di Revel class guided-missile frigate FFG 1 In Service Canadian Armed Forces Italian Navy Argentine Navy Japanese Navy Royal Netherlands Navy