I think Paul (Cornwall) might be refering to your cables being round, making them look similar to 3-core flex from the outside.

Our cables in Britain are flat (or oval, really) with all the conductors laying side by side.

Here's the 4mm version of T&E (Twin & Earth), with stranded 4mm phase and neutral and a solid 2.5 bare earth wire:
[Linked Image from tlc-direct.co.uk]

Here's a 3-core-plus-earth, with solid 1.5mm wires (bare earth is 1.0):
[Linked Image from tlc-direct.co.uk]


[This message has been edited by pauluk (edited 10-19-2003).]