A four module set comprised of two core modules constructed and two wing pieces.  The main modules may be used independently and connected to as a FreeMo series using connection points “1” and “2”.  This approach requires that wing module “B” be omitted, however, module wing “A” may provide another connection to another FreeMo module at point “3” or may be used as an additional spur in operations.

Alternatively, if connection point “2” is not used, then module wing “B” may be added and one of the two siding may be used as an exchange spur for up to two cars.  One siding must always be kept clear for operations.