Citizen Promaster Diver Automatic vs Seiko Prospex Samurai

Side-by-side comparison of specifications and features

CitizenPromaster Diver Automatic

NY0040-09E

SeikoProspex Samurai

SRPB51

Key Differences

Best Value

Citizen Promaster Diver Automatic (NY0040-09E)

Starting from $265

Price Comparison

Citizen Promaster Diver Automatic

MSRP

$400

New

$265

Used

$320

Seiko Prospex Samurai

MSRP

$525

New

$529

Used

$402

MSRP New (Amazon) Used (eBay)

Comparison of Citizen Promaster Diver Automatic, Seiko Prospex Samurai
Specification	Citizen Promaster Diver Automatic	Seiko Prospex Samurai
Pricing
MSRP	$400	$525
New Price	$265	$529
Used Price (Low)	$320	$402
Used Price (High)	$1,091	$632
30-Day Trend	↑ +0.6%	↑ +28.3%
Used Price Range	$320 - $1,091	$402 - $632
Identity
Reference	NY0040-09E	SRPB51
Nickname	N/A	N/A
Style	Diver, Tool	Diver, Tool
Release Era	2020s	2010s
Dimensions
Diameter	42mm	43.8mm
Thickness	N/A	13.4mm
Lug Width	N/A	22mm
Lug to Lug	N/A	48mm
Movement
Movement	Automatic	Automatic
Power Reserve / Battery	N/A	N/A
Accuracy	N/A	N/A
Case
Case Material	Stainless Steel	Stainless Steel
Crystal	Mineral Crystal	Hardlex
Water Resistance	200m (diving)	200m (diving)
Bezel	Unidirectional rotating	Unidirectional rotating
Dial
Dial Color	Black	Blue
Luminous	Yes	Yes
Community
Review Rating	N/A	N/A
In Collections	N/A	N/A
On Wishlists	N/A	N/A
Forum Threads	N/A	N/A

Quick Summary

If you are deciding between Citizen Promaster Diver Automatic and Seiko Prospex Samurai, the real decision is usually about wrist presence versus easier fit, entry price versus premium finishing or specs. They both touch the diver and tool use case, so smaller spec differences can matter more than brand preference.

How to choose

The biggest practical difference is usually movement and upkeep. Start with wrist fit and movement preference, then use water resistance and price to break the tie.

Citizen Promaster Diver Automatic

Citizen Promaster Diver Automatic is a better fit for smaller wrists, mechanical-watch enthusiasts, diver styling.

Seiko Prospex Samurai

Seiko Prospex Samurai is a better fit for buyers who want more wrist presence, mechanical-watch enthusiasts, diver styling.

Key Differences

Movement and upkeep

Citizen Promaster Diver Automatic: automatic movement

Seiko Prospex Samurai: automatic movement

Both use the same movement type, so maintenance differences are limited and fit or feature details should decide the purchase.

Size and wearability

Citizen Promaster Diver Automatic: 42mm

Seiko Prospex Samurai: 43.8mm · L2L 48mm

Fit is a real separator here — compare case width and lug-to-lug before deciding, especially if wrist comfort matters more than headline features.

Water resistance

Citizen Promaster Diver Automatic: 200m

Seiko Prospex Samurai: 200m

Water resistance is similar on paper, so focus on fit, features, and price instead.

Price and value

Citizen Promaster Diver Automatic: $265

Seiko Prospex Samurai: $525

There is a real price gap here — treat the more expensive option as an upgrade decision and confirm whether the extra spend buys something you will notice in weekly use.

Style and use case

Citizen Promaster Diver Automatic: diver

Seiko Prospex Samurai: diver

Both lean into a similar diver use case — the choice is more about fit, features, and price than category.

Crystal and materials

Citizen Promaster Diver Automatic: mineral crystal · steel

Seiko Prospex Samurai: Hardlex crystal · steel

Crystal choice can change long-term wear expectations — one may prioritize scratch resistance while the other keeps cost or vintage feel in check.

Choose Citizen Promaster Diver Automatic If...

You want the lower current entry price.

Choose Seiko Prospex Samurai If...

You are comfortable paying more for a stronger feature set.

Price and Value Notes

Citizen Promaster Diver Automatic is often the value play at current pricing, while Seiko Prospex Samurai makes more sense if you will use its extra features regularly.

There is a real price gap here — treat the more expensive option as an upgrade decision and confirm whether the extra spend buys something you will notice in weekly use.

Where to Check Deals

Check current deals on Amazon and eBay using the buttons below — listing prices, seller quality, and condition can change quickly.

Check current deals on Amazon and eBay

Prices change often, so compare the latest listings and condition options before you buy.

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Citizen Promaster Diver Automatic

Check Price on AmazonOpens in new tab · Price may vary

Check Price on eBayFrom $415 · Live listings

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Seiko Prospex Samurai

Check Price on AmazonOpens in new tab · Price may vary

Check Price on eBayFrom $510 · Live listings

Affiliate links — WatchCompared earns a commission on qualifying purchases. This doesn't affect your price.

Comparison FAQ

Which one is better for smaller wrists?

Start with case width and lug-to-lug. The watch that looks smaller on paper is often the safer choice, but lug shape and thickness still affect how it wears.

Which is better for swimming or rough daily wear?

Use the water resistance row as the first filter. Higher ratings generally give more flexibility for swimming and water exposure, but strap choice and overall condition still matter.

Should I choose based on price alone?

Price matters, but the better buy is the watch that matches your fit, feature priorities, and use case. Check live listings first, then decide whether the price gap actually changes the ownership experience.