San Martin SN0123 GMT vs Mido Ocean Star GMT

Both are GMT watches. In short: the San Martin SN0123 GMT wears 39mm vs the Mido Ocean Star GMT's 44mm — choose by wrist size. The San Martin SN0123 GMT is automatic, 200m water resistance, 39mm, sapphire crystal; the Mido Ocean Star GMT is automatic, 200m water resistance, 44mm, sapphire crystal.

Last verified 2026-06-27 · specs from manufacturer data · tier = price band, confirm the live price at the retailer

Spec	San Martin SN0123 GMT	Mido Ocean Star GMT
Movement	Automatic	Automatic
Water resistance	200m	200m
Case size	39mm	44mm
Crystal	sapphire	sapphire
Style	GMT / travel	GMT / travel
Price tier	Mid	Upper

Which should you buy?

The San Martin SN0123 GMT wears 39mm vs the Mido Ocean Star GMT's 44mm — choose by wrist size
The San Martin SN0123 GMT sits in the lower price tier (Mid) if budget leads

Where to buy

San Martin SN0123 GMTSee price on AmazonCheck price

Mido Ocean Star GMTSee price on AmazonCheck price

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FAQ

What's the difference between the San Martin SN0123 GMT and the Mido Ocean Star GMT?
Both are GMT watches. The San Martin SN0123 GMT is automatic, 200m water resistance, 39mm, sapphire crystal; the Mido Ocean Star GMT is automatic, 200m water resistance, 44mm, sapphire crystal.

Which is better value, the San Martin SN0123 GMT or the Mido Ocean Star GMT?
The San Martin SN0123 GMT is the lower-priced tier; the other steps up in build for more money — confirm both live prices at the retailer.

Citing these specs? Go ahead — manufacturer data, last verified 2026-06-27. Copy a ready-made reference:

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