The sub then, not too huge (227 x 170 x 227mm), nice and what you expect looks wise from a sub, but again plastered with a cheap screaming logo, which downgrades the aesthetics This sub has a 5.25in driver, it provides a bit of a bass that typically two speakers cannot provide. It is bass-reflex. However, do not expect immense pounding as it will distort quickly.
The subwoofer unit houses the power supply unit, the amplifier for the sub itself, and amplification circuits for the two-way satellite speakers. Bass can be adjusted via a dial on the sub.
On the backside the wiring is located, a power connector, speaker connections, and that Bass control are what you'll get. Once RCA cable connects to a speaker, the other DIN cable has leads to a headphones connector etc and connects to the other satellite speaker.