Citizen Tsuyosa Automatic (Green Dial) vs Seiko Prospex "Turtle"
Citizen's timepiece meets Seiko's diver
Quick Verdict
The Citizen Tsuyosa Automatic (Green Dial) ($250–$500) offers Citizen/Miyota In-House Automatic precision in the tier below the Seiko Prospex "Turtle" ($500–$1,000). The Tsuyosa Automatic (Green Dial) measures 40mm and is rated 50m (5 ATM). The Prospex "Turtle" counters with Made in Japan craftsmanship and 200m (20 ATM) Diver water resistance. Both are exceptional watches for their respective tiers.
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Specifications Compared
| Feature | Citizen Tsuyosa Automatic (Green Dial) | Seiko Prospex "Turtle" |
|---|---|---|
| Price | $250–$500 | $500–$1,000 |
| Case Size | 40mm | 45mm |
| Movement | Automatic Caliber 8210 | Automatic Caliber 4R36 |
| Caliber Type | Citizen/Miyota In-House Automatic | In-House Automatic Manufacture |
| Power Reserve | 40 Hours | 41 Hours |
| Water Resistance | 50m (5 ATM) | 200m (20 ATM) Diver |
| Crystal | Sapphire Crystal with Cyclops | Sapphire Crystal |
| Case Material | Stainless Steel | Stainless Steel |
| Origin | Made in Japan | Made in Japan |
Category-by-Category Analysis
Design & Aesthetics
Citizen's design language vs Seiko's approach
The Citizen Tsuyosa Automatic (Green Dial) features a Stainless Steel case at 40mm with Sapphire Crystal with Cyclops protection. The Seiko Prospex "Turtle" offers Stainless Steel construction at 45mm with Sapphire Crystal. Both represent their brand's distinct design philosophy and heritage.
Movement & Performance
Automatic Caliber 8210 vs Automatic Caliber 4R36
The Tsuyosa Automatic (Green Dial) runs the Automatic Caliber 8210 (Citizen/Miyota In-House Automatic, 40 Hours power reserve) at 21,600 vph (3 Hz) frequency. The Prospex "Turtle" uses the Automatic Caliber 4R36 (In-House Automatic Manufacture, 41 Hours reserve) at 21,600 vph (3 Hz). The Prospex "Turtle" offers a longer power reserve.
Wearability & Fit
40mm vs 45mm — different wrist presence
At 40mm, the Tsuyosa Automatic (Green Dial) wears more compactly on smaller wrists compared to the Prospex "Turtle" at 45mm. Water resistance differs: 50m (5 ATM) vs 200m (20 ATM) Diver.
Value & Cost of Ownership
Citizen sits in the lower tier
The Citizen Tsuyosa Automatic (Green Dial) sits at $250–$500 and the Seiko Prospex "Turtle" at $500–$1,000. On the specs that outlast any price: the Tsuyosa Automatic (Green Dial) uses Sapphire Crystal with Cyclops with 40 Hours, against Sapphire Crystal and 41 Hours on the Prospex "Turtle". Service intervals are typically 5-7 years for both.
Water Resistance
50m (5 ATM) vs 200m (20 ATM) Diver
The Tsuyosa Automatic (Green Dial) is rated to 50m (5 ATM) while the Prospex "Turtle" handles 200m (20 ATM) Diver. The Prospex "Turtle" offers superior water resistance.
Our Verdict
Citizen
Tsuyosa Automatic (Green Dial)
Choose the Citizen Tsuyosa Automatic (Green Dial) if you prioritize Citizen/Miyota In-House Automatic engineering, Made in Japan craftsmanship, and 50m (5 ATM) water resistance. At $250–$500, it delivers Automatic Caliber 8210 with 40 Hours power reserve.
Check Price on AmazonSeiko
Prospex "Turtle"
Choose the Seiko Prospex "Turtle" if you value In-House Automatic Manufacture technology, Made in Japan heritage, and 45mm proportions. At $500–$1,000, the Automatic Caliber 4R36 with 41 Hours power reserve makes it a compelling choice.
Check Price on AmazonThe Bottom Line
The Citizen Tsuyosa Automatic (Green Dial) and Seiko Prospex "Turtle" represent two distinct approaches to fine watchmaking — the Citizen bringing Made in Japan tradition while Seiko delivers Made in Japan engineering.
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.