Does anybody know anything about Q-T valve lash adjusting screws ?

I bought a set on EBay and they work fine in my 235.

I replaced them with standard screws as I was concerned about the small spring loaded ball ending up in the engine.
I can’t find anything out about them other than there’s some NOS on EBay and they may have not been manufactured after 1946.

Has anyone had long term experience with them fitted?
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Last edited by Gdads51; 07/19/2025 2:18 AM. Reason: remove image link in text to allow to display in AM
1955 2nd Series 1/2-ton
"Bolting in New Zealand"
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