On Wed, 24 May 2017 22:30:52 +0100, Graeme wrote:

Just to bring this full circle, having now purchased some modern Pozi
screws, I'm delighted to say that my original and ancient GKN drivers
are a perfect fit.

They should be.

Not surprising, given that one of the links supplied
quoted GKN as the inventor of Pozi.

If it said that GKN were the inventor then it was incorrect, GKN licenced the
design from the Philips Screw Company.

The trademark was first registered in 1960

https://trademarks.justia.com/720/91...-72091320.html

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