Bricks are geographic units that are used to define Reps’ territory i.e. a Rep can cover multiple bricks, partial brick allocation also being possible. In some affiliates the bricks are the counties of that country. Bricks are automatically populated from the external Customer Database. The link between Customers and Bricks is the customer addresses, each address must contain the brick information.
In CEX360 we can view and search the existing Bricks from the Setup -> Bricks menu:

Accesing the Bricks list
We can also add or edit the external Id of a brick by clicking on a brick and completing the External Id field:

Edit Brick details form