In article , Brian Sharrock
wrote:
And available in a variety of lengths from 'proper'
electricians' suppliers.

25mm - 80mm in 5mm steps across the road from here.

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Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
Free SEDBUK boiler database browser http://www.sda.co.uk/qsedbuk.htm