"Sheffield" hub ?
 

No listing in Velobase, no hits on google. Is laced to a Weinmann 27" clincher, was on a bike-boom basic Torpado, so that and the Simplex bit are period correct but quite possibly changes from the original equipment as other bits - rear wheel, brakes, crankset are clearly later changes.

Gnutti re-brand?


https://cimg8.ibsrv.net/gimg/bikefor...0e725c94e8.jpg

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one parts maker who employed this name was Noli-Cattaneo

have not heard of them offering hubs

if a contract build as you suggest perhaps it was done for them
[MENTION=57649]iab[/MENTION] may be able to shed some of his considerable illumination here...


https://cimg5.ibsrv.net/gimg/bikefor...f2f7cfe293.jpg

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should you have a Gnutti from this era on hand you could pull the axles sets and compare them side-by-side

the final year for this model of Juy QR skewer was 1971

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