Baltic Aquascaphe vs Seiko Prospex Sumo SPB103

Both are dive watches in the upper tier. In short: the Baltic Aquascaphe wears 39mm vs the Seiko Prospex Sumo SPB103's 45mm — choose by wrist size. The Baltic Aquascaphe is automatic, 200m water resistance, 39mm, sapphire crystal; the Seiko Prospex Sumo SPB103 is automatic, 200m water resistance, 45mm, sapphire crystal.

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

Spec	Baltic Aquascaphe	Seiko Prospex Sumo SPB103
Movement	Automatic	Automatic
Water resistance	200m	200m
Case size	39mm	45mm
Crystal	sapphire	sapphire
Style	Dive	Dive
Price tier	Upper	Upper

Which should you buy?

The Baltic Aquascaphe wears 39mm vs the Seiko Prospex Sumo SPB103's 45mm — choose by wrist size.

Where to buy

Baltic AquascapheSee price on AmazonCheck price

Seiko Prospex Sumo SPB103See price on AmazonCheck price

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FAQ

What's the difference between the Baltic Aquascaphe and the Seiko Prospex Sumo SPB103?
Both are dive watches in the upper tier. The Baltic Aquascaphe is automatic, 200m water resistance, 39mm, sapphire crystal; the Seiko Prospex Sumo SPB103 is automatic, 200m water resistance, 45mm, sapphire crystal.

Which is better value, the Baltic Aquascaphe or the Seiko Prospex Sumo SPB103?
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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