Seiko · Prospex Samurai Special Edition · Ref SRPF03
43.8mm of edges.
The bigger Samurai. A 43.8mm faceted case, 13.4mm thick, 201g on the bracelet, with a 200m diver’s rating and the hacking, hand-winding 4R35 inside. It wears like the tool it is.
Water resistance
200m
https://www.seikowatches.com/us-en/products/prospex/srpf03
Case
43.8mm · 13.4mm
48.4mm lug to lug, 22mm lugs, 201g
Movement
4R35
Hacking and hand-winding, 23 jewels
Power reserve
41 hours
https://www.seikowatches.com/us-en/products/prospex/srpf03
Crystal
Hardlex
Flat
Built for a wetsuit
Seiko lists the SRPF03 at 43.8mm across, 13.4mm thick and 48.4mm lug to lug, weighing 201g on its steel bracelet. Those are big numbers and they are the point. The three-fold clasp locks, releases with push buttons and carries a diver’s extension.
The lug width is 22mm, which opens up rubber and NATO straps if the bracelet is too much. On a wrist under about 6.75 inches the case will likely overhang; try a 44mm watch before ordering.
The blade dial
The hour hand is shaped like a katana blade and the markers are faceted to match the case. A large shield-shaped marker sits at twelve. The bezel is black, unidirectional and angular in profile, with a lumed pip at zero. LumiBrite covers hands, markers and pip.
The date sits at three with black text on white. The crown is screw-down at four o’clock. This is a Special Edition of the Samurai line, and Seiko’s page describes it as such.
The 4R35, again
Seiko’s 4R35 automatic runs at 21,600 vibrations per hour on 23 jewels with a stated 41-hour reserve. Unlike the older 7S26 it hacks and hand-winds, so it sets to the second and tops up from the crown.
Seiko’s figures are the ones printed here. Nothing has been timed or measured for this page.
Specs
- Reference
- SRPF03
- Case size
- 43.8mm
- Case material
- Stainless Steel
- Movement
- Automatic Caliber 4R35
- Caliber type
- Seiko Automatic, hand-winding and hacking
- Crystal
- Hardlex Crystal
- Water resistance
- 200m (20 ATM)
- Power reserve
- 41 Hours
- Complications
- Date, Uni-Directional Dive Bezel
- Jewels
- 23 Jewels
- Frequency
- 21,600 vph (3 Hz)
- Origin
- Japanese Movement
Specifications as published by Seiko. We research from manufacturer documentation and published sources rather than hands-on testing. Researched 2026-09-03.
Verdict
A full-sized 200m Samurai with a blade-hand dial and every figure confirmed by Seiko, for people whose wrists can carry 43.8mm.
Strengths
- 200m diver’s rating, screw-down crown, diver’s extension
- Faceted case and blade hands that look like nothing else at the price
- 4R35 with hacking and hand-winding
- 22mm lugs make strap swaps easy
Trade-offs
- 43.8mm and 201g is a lot of watch
- Hardlex, not sapphire
- 41-hour reserve
- Date only
Buy it if
A diver or a large-wristed daily wearer who wants an aggressive case shape with real dive credentials.
Skip it if
Your wrist is under 6.75 inches, or you want a slim watch under a cuff. The 41.7mm SRPL13 Samurai is the smaller option.
FAQ
Seiko lists 43.8mm across, 13.4mm thick and 48.4mm lug to lug, with 22mm lugs. It weighs 201g on the bracelet and wears large.
Sources
Researched and last updated 2026-09-03. We do not test watches in hand; every figure above is traceable to the manufacturer or the sources listed here.
Seiko Prospex Samurai SRPF03
Reference SRPF03 · $250–$500
Prices and availability change; the band above is a research figure, so check the current listing.
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