The Colt Mk 12 is a 20 mm autocannon that was widely used by the United States Navy after World War II.

The Mk 12 was an advanced derivative of the wartime Hispano HS 404 that was used on French, British and some American fighter aircraft during World War II.

It used a lighter projectile with a bigger charge for better muzzle velocity and higher rate of fire at the cost of hitting power.

Pilots of the F-8 Crusader over North Vietnam, in particular, appreciated the presence of the cannon, but jams and stoppages were common, especially following hard dogfighting maneuvers in high-g environments.

International customers of the A-4 Skyhawk, F-8 Crusader, and the A-7 Corsair II also used the Mk 12 cannon: Argentina, Australia, Brazil, France, Kuwait, Malaysia, New Zealand, the Philippines and Portugal.