Thanks chaps looks like I can repair my u/s ones then. Julian I can see why I have had so many failures. Clearly the ones that I have are not the real thing.
cyclobutch:
I can advise that this is a particularly weak area on some Chinese sourced copies.
Aint that the truth - mind you its not always clear which ones are the real thing, in fact is the real thing still available?
Greybeard:
Nuts with the sleeve are available
Splendid stuff, never seen those before. I will get some.