What does the GMT function do?

A fourth hand tracks a second time zone against the 24-hour bezel. It is useful for travel or for keeping an eye on another city.

Can I swim and dive with it?

Yes. It is rated to 300m with a screw-down crown, so it suits swimming and recreational diving.

The GMT adds a second time zone and a 24-hour bezel. It is slightly thicker and busier than the three-hand diver.

The steel bracelet has a folding clasp. Owners note the clasp is fairly basic, so sizing may need a dealer.

It runs a Longines automatic movement with a long power reserve, visible through the caseback on most versions.

Travelers and divers who want one watch for both, and buyers who want Swiss GMT specs without premium-brand pricing.

At Vintage Thread Box, for $267.80, as of our latest check.

Rated 5 out of 5 from 3 ratings.

$267.80at Vintage Thread BoxChecked Nov 9

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