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Citizen Promaster Diver BN0150 vs Seiko Prospex Samurai SRPB51

Both are dive watches in the mid tier. In short: the Seiko Prospex Samurai SRPB51 is mechanical (automatic) for the enthusiast feel and no battery; the Citizen Promaster Diver BN0150 is solar / light-powered for accuracy and low maintenance. The Citizen Promaster Diver BN0150 is solar / light-powered, 200m water resistance, 44mm, mineral crystal; the Seiko Prospex Samurai SRPB51 is automatic, 200m water resistance, 43.8mm, hardlex crystal.

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

SpecCitizen Promaster Diver BN0150Seiko Prospex Samurai SRPB51
MovementSolar / light-poweredAutomatic
Water resistance200m200m
Case size44mm43.8mm
Crystalmineralhardlex
StyleDiveDive
Price tierMidMid

Which should you buy?

The Seiko Prospex Samurai SRPB51 is mechanical (automatic) for the enthusiast feel and no battery; the Citizen Promaster Diver BN0150 is solar / light-powered for accuracy and low maintenance.

Where to buy

Citizen Promaster Diver BN0150See price on AmazonCheck price

Seiko Prospex Samurai SRPB51See price on AmazonCheck price

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FAQ

What's the difference between the Citizen Promaster Diver BN0150 and the Seiko Prospex Samurai SRPB51?
Both are dive watches in the mid tier. The Citizen Promaster Diver BN0150 is solar / light-powered, 200m water resistance, 44mm, mineral crystal; the Seiko Prospex Samurai SRPB51 is automatic, 200m water resistance, 43.8mm, hardlex crystal.

Which is better value, the Citizen Promaster Diver BN0150 or the Seiko Prospex Samurai SRPB51?
Both sit in the mid 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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