General mono subwoofer cables for most sub systems for surround, where the amplifier has a dedicated subwoofer connection.
When connecting a subwoofer, e.g. to a home theatre system, there are usually one or more outputs for active subwoofers. Sub-outputs are usually only 1 Phono RCA connector, as the signal is mono, also called the LFE channel, which makes up X.1 in the naming of a 5.1 or 7.1 surround setup. If there are more subwoofer outputs on the surround receiver, these are also in mono, it is possible to connect multiple subwoofers. The latter is for e.g. 7.2 and 9.2 receivers etc.
The subwoofer cable is connected to the subwoofer's LFE or mono input. If the sub has both a right and left input without any being labelled LFE or mono, we recommend a subwoofer Y-split cable to be sure to get the best performance, again if it is a mono output on the receiver.
If you want to connect a stereo amplifier with stereo pre-out to a subwoofer, we recommend that you use a normal stereo phono cable.