Airlock
Airlocks will be required to access the settlement from the Martian surface, or to connect up vehicles to one another or to habitats.
A rectangular airlock port with a double set of connectors can provide circuit redundancy as well as androgynous connections between any pair of airlocks. Centering would need to be done mostly using an adjustable suspension on vehicles, although the facing connection could have about 15 degrees of travel and perhaps up to 20 cm of travel in a flexible bellow sleeve.
The airlock port shown is 1.2 m wide x 2.2m high.
Existing ports
Berthing ports and docking ports already exist for the ISS and all space vehicles, but these are relatively small or poorly configured for gravity. They are also often male or female, making them useless for ship to ship connections, or preventing inversions of connections.