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Prospex · Sea

Seiko SRPE99

Ref. SRPE99 · In production

  • Case45 mm
  • Thick13.4 mm
  • Water res.200 m
  • MovementAutomatic
  • CrystalHardlex (mineral)
New (US list price)$575Source: seikowatches.com, checked 29 Oct 2026Check price on Amazon →Paid link · disclosure
Wrist fitChecking…

Uses the same sizing guide as Watch Finder. A guide, not a rule.

Seiko SRPE99 size, specs and price at a glance

The Seiko SRPE99 is 45 mm wide and 13.4 mm thick. Seiko does not publish its lug-to-lug length. It takes 22 mm straps and ships on a bracelet. Inside is the 4R36 automatic calibre, water resistant to 200 m. US list price: $575 when we last checked seikowatches.com (29 Oct 2026).

Strap shopping? See our lug width chart.

Overview

The Seiko SRPE99 is a diver watch from the Prospex collection, part of the Sea family. It has a 45 mm case, 13.4 mm thick. Inside is an automatic movement (calibre 4R36) with 41 h of power reserve. You also get 200 m water resistance, a hardlex (mineral) crystal and a bracelet.

Who it suits

  • Wrists of roughly 18.1–20.0 cm (7.1–7.9 in), by our Watch Finder sizing guide
  • Swimming, snorkelling and diving

Strengths

  • Certified to the ISO 6425 diver's standard (200 m)
  • Screw-down crown helps keep water out
  • Hacks and hand-winds, so it is easy to set

Trade-offs

  • Hardlex (mineral) crystal scratches more easily than sapphire
  • 41 h power reserve: it stops after about a day and a half off the wrist
  • Heavy at 195 g

Written by Watch.co from the published specs below. These are not owner reviews.

Full specifications

Case

Case diameter45 mmseikowatches.com · 29 Oct 2026
Thickness13.4 mmseikowatches.com · 29 Oct 2026
Lug-to-lugNot published by Seiko
CrystalHardlex (mineral)seikowatches.com · 29 Oct 2026
CasebackScrewseikowatches.com · 29 Oct 2026
BezelUnidirectional rotatingseikowatches.com · 29 Oct 2026
Water resistance200 mseikowatches.com · 29 Oct 2026
Screw-down crownYesseikowatches.com · 29 Oct 2026
ISO 6425 diverYesseikowatches.com · 29 Oct 2026
Weight195 gseikowatches.com · 29 Oct 2026

Dial

Luminous materialLumiBriteseikowatches.com · 29 Oct 2026
DateDay/Dateour classification

Strap / Bracelet

Bracelet / strapBraceletseikowatches.com · 29 Oct 2026
Lug width22 mmseikowatches.com · 29 Oct 2026

Other

US list price (MSRP)$575seikowatches.com · 29 Oct 2026
Production statusIn productionseikowatches.com · 29 Oct 2026
Style (our classification)Diverour classification

Specs are summarised in our own words from the brand's product page. Each row links its source and the date we checked it. Fields we haven't verified are left out rather than guessed.

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Questions about the Seiko SRPE99

How big is the Seiko SRPE99?

The case is 45 mm wide, 13.4 mm thick.

What movement does the Seiko SRPE99 use?

It uses the 4R36 calibre, a automatic movement with 41 h of power reserve.

Can I swim with the Seiko SRPE99?

Yes. It is rated to 200 m and certified as an ISO 6425 diver.

Does the Seiko SRPE99 have a date?

Yes, it shows the day and date.

How much is the Seiko SRPE99?

The US list price was $575 on seikowatches.com when we checked on 29 Oct 2026. Prices change, so check before you buy.

Will the Seiko SRPE99 fit my wrist?

By our sizing guide it sits best on wrists of about 18.1–20.0 cm (7.1–7.9 in). Use the fit checker on this page to test your own wrist.

Watch.co is independent and not affiliated with any brand. Brand names are used only to identify products.