Seiko Vintage 6117-6400 World Time GMT Automatic Error Dial Bracelet 41mm

But not all mistakes are what they seem. They work on the basis of a revolving city ring around the outside of the dial and a fixed 24-hour hand.

One has GMT aligned with London, as you might expect, and the other, often referred to as an "error dial", has London aligned with Paris an hour ahead.

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