Casio G-Shock DW-5600 Square vs Seiko Prospex "Turtle"
Two divers compared — $50–$100 vs $500–$1,000
Quick Verdict
The Casio G-Shock DW-5600 Square ($50–$100) offers Casio Digital Quartz (Battery) precision in the tier below the Seiko Prospex "Turtle" ($500–$1,000). The G-Shock DW-5600 Square measures 42.8mm (Square) and is rated 200m (20 ATM). The Prospex "Turtle" counters with Made in Japan craftsmanship and 200m (20 ATM) Diver water resistance. Both are exceptional divers for their respective tiers.
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Specifications Compared
| Feature | Casio G-Shock DW-5600 Square | Seiko Prospex "Turtle" |
|---|---|---|
| Price | $50–$100 | $500–$1,000 |
| Case Size | 42.8mm (Square) | 45mm |
| Movement | Quartz Module 3229 | Automatic Caliber 4R36 |
| Caliber Type | Casio Digital Quartz (Battery) | In-House Automatic Manufacture |
| Power Reserve | 2-Year Battery | 41 Hours |
| Water Resistance | 200m (20 ATM) | 200m (20 ATM) Diver |
| Crystal | Mineral Glass | Sapphire Crystal |
| Case Material | Resin | Stainless Steel |
| Origin | Casio (Japan) | Made in Japan |
Category-by-Category Analysis
Design & Aesthetics
Casio's design language vs Seiko's approach
The Casio G-Shock DW-5600 Square features a Resin case at 42.8mm (Square) with Mineral Glass 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
Quartz Module 3229 vs Automatic Caliber 4R36
The G-Shock DW-5600 Square runs the Quartz Module 3229 (Casio Digital Quartz (Battery), 2-Year Battery power reserve) at standard 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
42.8mm (Square) vs 45mm — different wrist presence
At 42.8mm (Square), the G-Shock DW-5600 Square wears more compactly on smaller wrists compared to the Prospex "Turtle" at 45mm. Water resistance differs: 200m (20 ATM) vs 200m (20 ATM) Diver.
Value & Cost of Ownership
Casio sits in the lower tier
The Casio G-Shock DW-5600 Square sits at $50–$100 and the Seiko Prospex "Turtle" at $500–$1,000. On the specs that outlast any price: the G-Shock DW-5600 Square uses Mineral Glass with 2-Year Battery, against Sapphire Crystal and 41 Hours on the Prospex "Turtle". Service intervals are typically 5-7 years for both.
Water Resistance
200m (20 ATM) vs 200m (20 ATM) Diver
The G-Shock DW-5600 Square is rated to 200m (20 ATM) while the Prospex "Turtle" handles 200m (20 ATM) Diver. Both offer identical water resistance ratings.
Our Verdict
Casio
G-Shock DW-5600 Square
Choose the Casio G-Shock DW-5600 Square if you prioritize Casio Digital Quartz (Battery) engineering, Casio (Japan) craftsmanship, and 200m (20 ATM) water resistance. At $50–$100, it delivers Quartz Module 3229 with 2-Year Battery 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 Casio G-Shock DW-5600 Square and Seiko Prospex "Turtle" represent two distinct approaches to the diver category — the Casio bringing Casio (Japan) tradition while Seiko delivers Made in Japan engineering.
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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.