1971 - Mark 45 Mod 0 1980 - Mark 45 Mod 1 1988 - Mark 45 Mod 2 Specifications 19weight (tn) 127caliber (mm) 20Rate of fire (round/min) 24range (km) Used by 1974 California class guided-missile cruiser (nuclear powered) CGN 21975 Spruance class destroyer DD 21976 Virginia class guided-missile cruiser (nuclear powered) CGN 21981 Kidd class guided-missile destroyer DDG 21983 Ticonderoga class guided-missile cruiser CG 21991 Arleigh Burke Flight I class guided-missile destroyer DDG 11992 Hydra class frigate FF 21996 Anzac class frigate FF 12002 F100 Alvaro de Bazan guided-missile destroyer DDG 1 In Service US Navy Hellenic Navy Royal Australian Navy Royal New Zealand Navy Spanish Navy
Mark 45 5/54 inch (127mm)
Hydra class frigate FF 
Anzac class frigate FF 
F100 Alvaro de Bazan guided-missile destroyer DDG 
Royal New Zealand Navy