All units representing ships and that need to be deployed in naval bases. Ships cannot upgrade to newer models, once researched. The only exception is that the CAG of a Carrier can upgrade to newer models, but not the carrier vessel itself.
- Submarine (SS). A submarine does not need screens to operate efficiently.
- Transports (TP). These ships are very vulnerable and cannot attack in combat. They transport troops to operate an amphibious invasion.
- Carrier Air Group (CAG). They represent the planes of carrier. Only a CV can hold this brigade and no other ship may.
All capital ships except a CV and a CVL may hold any of these brigades.
Screen ships, additionally, can be outfitted with an additional brigade type.
- Anti-Submarine Warfare (ASW).