On the back side are 2 jack sockets which are designed to connect amplifier or another cabinet. Thanks to that, one can avoid using long connecting cables between the cabinets and the amplifier in a “chain” usage.
Use of two speakers effected that the tone is better than cabinets with 4 speakers and it is not so troublesome. A set of two 212 cabinets is more universal than a 412 cabinet itself.
To an individual order, it is possible to install other speakers or grill cloth.