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Squale 1521 vs Marathon GSAR

Both are dive watches in the upper tier. In short: the Squale 1521 wears 42mm vs the Marathon GSAR's 41mm — choose by wrist size. The Squale 1521 is automatic, 300m water resistance, 42mm, sapphire crystal; the Marathon GSAR is automatic, 300m water resistance, 41mm, sapphire crystal.

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

SpecSquale 1521Marathon GSAR
MovementAutomaticAutomatic
Water resistance300m300m
Case size42mm41mm
Crystalsapphiresapphire
StyleDiveDive
Price tierUpperUpper

Which should you buy?

The Squale 1521 wears 42mm vs the Marathon GSAR's 41mm — choose by wrist size.

Where to buy

Squale 1521See price on AmazonCheck price

Marathon GSARSee price on AmazonCheck price

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FAQ

What's the difference between the Squale 1521 and the Marathon GSAR?
Both are dive watches in the upper tier. The Squale 1521 is automatic, 300m water resistance, 42mm, sapphire crystal; the Marathon GSAR is automatic, 300m water resistance, 41mm, sapphire crystal.

Which is better value, the Squale 1521 or the Marathon GSAR?
Both sit in the upper tier, so it comes down to movement, water resistance and case size — see the spec table above.

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

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