Phalanx

Mk15 Block 1B Phalanx Close-In-Weapon-System (CIWS)
Function
Anti-ship missile defence
Manufacturer Raytheon Systems
Weight 5625 kilograms
Rate of Fire
4500 rounds per minute
Caliber
20 millimetre
Usage Destroyer, Guided Missile (DDG)

The Phalanx Close-In Weapons System (CIWS) provides Royal Australian Navy ships with a rapid-fire, computer controlled, radar guided gun system for defence against anti-ship missiles.