I was not brave enough to reuse the late style keepers, got mine from CycleX.
But I gave some of my old valves to Davidov and he used them in his build and all seems to be ok.
My take is that in extreme situations, the late style keepers could fail, but I still was not brave enough to use them.
I assume you have this, right?

May i know from what book is this 70cb750?
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