Updated
Seiko Turtle vs Seiko Samurai
Cushion case or angular case, both Prospex 200m
Quick Verdict
The Seiko Prospex Turtle SRPE05 and the Samurai SRPL13 are both 200m automatic divers in the $500–$1,000 band with 41-hour reserves. The Turtle is a 45mm cushion case with a sapphire crystal, a day-date and the 4R36. The Samurai is a 41.7mm angular case with Hardlex, a date and the 4R35. The Samurai is the smaller wear; the Turtle has the harder crystal.
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Specifications Compared
| Feature | Seiko Prospex "Turtle" | Seiko Prospex Samurai SRPL13 |
|---|---|---|
| Price | $500–$1,000 | $500–$1,000 |
| Case Size | 45mm | 41.7mm |
| Movement | Automatic Caliber 4R36 | Automatic Caliber 4R35 |
| Caliber Type | In-House Automatic Manufacture | Seiko In-House Automatic |
| Power Reserve | 41 Hours | 41 Hours |
| Water Resistance | 200m (20 ATM) Diver | 200m (20 ATM) |
| Crystal | Sapphire Crystal | Hardlex Crystal |
| Case Material | Stainless Steel | Stainless Steel |
| Origin | Made in Japan | Made in Japan |
Category-by-Category Analysis
Design & Aesthetics
Rounded cushion against sharp angles
The Turtle's cushion case is a 1970s Seiko shape, soft and rounded. The Samurai is all angles and facets. Same purpose, opposite personalities.
Movement & Performance
4R36 day-date against 4R35 date
The Turtle runs the 4R36, 24 jewels, with a day-date. The Samurai runs the 4R35, 23 jewels, with a date. Both run at 21,600 vph with a 41-hour reserve. The only practical difference is the day display.
Durability & Water Resistance
Same 200m, sapphire on the Turtle
Both are rated to 200m (20 ATM). The Turtle's listed crystal is sapphire; the Samurai uses Hardlex, Seiko's hardened mineral glass. Sapphire resists scratches better.
Wearability & Fit
The Samurai is 3.3mm smaller
The Samurai is 41.7mm and the Turtle is 45mm. The Samurai is the easier fit on wrists under about 7 inches.
Value & Cost of Ownership
Same band
Both sit in the $500–$1,000 band. Pick on case shape and size rather than price.
Our Verdict
Seiko
Prospex "Turtle"
Choose the Turtle if you have a medium to large wrist and want the sapphire crystal and day-date. It is a big watch, so it suits medium and larger wrists best.
Check Price on AmazonSeiko
Prospex Samurai SRPL13
Choose the Samurai if you want a sharper, more modern look in a smaller case. At 41.7mm it fits more wrists. The trade is Hardlex instead of sapphire.
Check Price on AmazonThe Bottom Line
The Seiko Prospex Turtle SRPE05 and Samurai SRPL13 are both 200m automatic dive watches with 41-hour reserves; the Turtle has a 45mm cushion case, sapphire crystal and day-date, while the Samurai has a smaller 41.7mm angular case with a Hardlex crystal and date only.
Frequently Asked Questions
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How This Page Was Made
Our comparisons are generated from a hand-maintained specification database and reviewed under our editorial standards. We use AI tools to assemble pages from that data. We don’t invent specs: every number traces back to the database, and when we correct an entry, the fix is applied site-wide. As an Amazon Associate, The Horologist earns from qualifying purchases.