The A-180-3 is a dual buffered 1-in-3 multiple. The signal applied to the input socker appears as a buffered signal at the three output sockets. Each output has it's own buffer, i.e. the three output sockets are not simply connected to each other. The lower output of the upper unit is normalled to the input of the lower unit. That way the module works as a single 1-in-6 buffered multiple provided that no signal is applied to the input of the lower unit.
Application: copying/buffering of control and audio signals.