From my dad's days as a generator mechanic, no doubt. It was made in England. Major diameter at the bezel is 99.4mm. It would fit in a 93mm diameter panel opening.
The logo on the dial face says, "NEWAGE GROUP". Newage Group these days appears to be a clothing manufacturer.
On the rear of the meter's case is "HOBUT". Hobut looks more like it.
I opened it up just for the heck of it. Here's a view of the meter's innards.
The terminals and coil are quite substantial, as one would expect for a 100 Amp meter.
A date revealed itself when I took the casing off -- it's "1959/2".
I'll give the grimy casing a good scrub, and put this away with some other spare gauges I have.
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