In article ,
John Rumm wrote:
I meant to say different models of TRV and the Market leader is
Dr*yt*n isn't it.

I found a Pegler ones that Screwfix sell whistle if on the return side -
even though in theory they work both ways.

My limited experience says only to buy the decent and therefore expensive
ones. Shed types fail after about 5 years.

--
*If a pig loses its voice, is it disgruntled?

Dave Plowman London SW
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