What is the Style for a Class B and a Class A Wiring Configuration of the MUX Bus?

Question

The D7039, Lot 100 or later provides either two, two-wire (Class “B”, Style 4) multiplex buses or one, four-wire (Class “A”, Style 6) multiplex bus.

In Class ”A” Mode, up to 120 additional addressable points can be added.
In Class “B” Mode, up to 240 additional addressable points can be added. Connects directly to the control panel, allowing one for each system.

Part numbers FPD-7024, D7024, DS9400, DS9400I, DS9400M,D7039, DS9431