Longines HydroConquest vs Sinn U1

Both are dive watches in the premium tier — here's how the specs differ and which to pick.

Last verified 2026-06-11 · specs from manufacturer data · tier = price band, confirm the live price at the retailer

Spec	Longines HydroConquest	Sinn U1
Movement	Automatic	Automatic
Water resistance	300m	300m
Case size	41mm	44mm
Crystal	sapphire	sapphire
Style	Dive	Dive
Price tier	Premium	Premium

Which should you buy?

• the Longines HydroConquest wears 41mm vs the Sinn U1's 44mm — choose by wrist size

Where to buy

Check the Longines HydroConquest price on Amazon →

Check the Sinn U1 price on Amazon →

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FAQ

What's the difference between the Longines HydroConquest and the Sinn U1?
Both are dive watches in the premium tier. The Longines HydroConquest is automatic, 300m water resistance, 41mm, sapphire crystal; the Sinn U1 is automatic, 300m water resistance, 44mm, sapphire crystal.

Which is better value, the Longines HydroConquest or the Sinn U1?
Both sit in the premium tier, so it comes down to movement, water resistance and case size — see the spec table above.

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