Prysmian 6943X Black 3-Core 4mm² Armoured Cable 25m Coil (67843)

Thank you for contacting Prysmian Group UK Technical Support. These cable types are not suitable for use as "extensions leads. These cables are for fixed wiring. We would recommend that you consult a qualified electrician who will be able to direct you to the most appropriate solution for your installation. Thank you Kind Regards UK Technical Support

Armoured cables are suitable for direct burial installations, so do not need to be installed in ducting, although you may wish to do so for easy of access/replacement in the future. Clause 522.8.10 in BS7671 refers. As this would appear to be a new circuit, consultation and final connection must be made with a Part P qualified electrician

The question is somewhat ambiguous, as it is not clear which cable you are looking to replace with the armoured cable. However, regardless, if you are referring to the ring main cable that feeds you sockets (twin and earth), then whilst armoured cable does provide some shielding, it is not a suitable cable for this application If you are looking to replace the actual lead that connects the cd player to the socket, then that cable is a flexible type cable, and again an armoured cable is not a suitable alternative for the application. If it this the cd player lead you are looking to replace, then we we suggest consulting with manufacturer for a suitable alternative cable lead, specially designed for this purpose, or perhaps a specialist Hi-Fi magazine

Any of the 20S type glands such as code 25996 will fit this cable as it's only 1mm thicker than the 2.5mm equivalent SWA.

Depends on how much power you want to run. In general 4mm can carry up to 32A, but it really depends on how it's installed and how long the run is, certainly no longer than 35 meters. If your heater has a 13A plug then you could go with 2.5mm which can easily cope with 13A and be fed from a 16 or 20A breaker, again depending on how it's installed.