Richard Sterry wrote:
Can anyone identify the type of non-return valve shown in this photo
please?

http://www.sterry.org.uk/temp/non-return_valve.jpg

I only looked inside briefly, but it appeared to consist of
something
rather like a semi-rigid plastic duck's bill - or perhaps more like
the flattened neck of those balloons that are designed to make a
very
loud (and rather rude) noise when released!

You will appreciate that searching for "non-return valve" is a bit
too
general, so a more specific generic or manufacturer's name would be
a
great help to me.

Many thanks

What's the application? It looks like a Hep2O waste trap, no u bend as
such but a plasic "fanny" that only lets the sink water one way. It is
a non return valve but am surprised to see the copper fitting in
there. What sort of back pressure are u expecting it to hold?
--
Richard