In article ,
Richard Russell writes:
This is more of a rant than a question... Why are there two similar
(but incompatible) lengths of 20W T4 slimline fluorescent tube - the
so-called 'Eterna' variety (as sold by B&Q) which is 578mm between the
ends of the pins, and the 'Standard' variety which is 567mm between
the ends of the pins?

There aren't any standards for T4 tubes, unfortunately.
Most fluorescent tube sizes were developed and standardised
in Europe and the US. T4's came from the far East, and there
are different ones from different manufacturers.

I've got a number of Omicron fittings which were sold by CPC,
Maplin, and some other places. AFAIK, these are no longer
available. I've got a stock of 16W tubes, and one spare 8W
and one spare 20W. When I run out of one of the sizes, I'll
probably have to replace the lot (as I won't be able to get
any matching colours). More recently, I've fitted the newer
T5HE and T5HO tubes (14W to 80W) as these are standardised,
and lengths match common kitchen unit widths (actually
they're designed to match modular ceiling tile sizes, but
it amounts to the same thing).

--
Andrew Gabriel
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