I think you need to clarify your requirements.
If theres only one switch, why would it be a two way I ask?
I'll bet you want switches at top and bottom of stairs.
How come you're asking when it's all given in the references at the top of 'electrics UK' I'll bet you didn't know it was there.
There's no way that he would know about the reference topic, or any topics, or the existence of this forum, as his posting came in via the "how to" page, not directly.
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