Casio Pro Trek PRW3500T-7 vs Seiko Prospex "Turtle"
Two divers compared — $250–$500 vs $500–$1,000
Quick Verdict
The Casio Pro Trek PRW3500T-7 ($250–$500) offers Tough Solar Quartz, Multi-Band 6 precision in the tier below the Seiko Prospex "Turtle" ($500–$1,000). The Pro Trek PRW3500T-7 measures 56.9 × 53.4 × 14.8mm 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 Pro Trek PRW3500T-7 | Seiko Prospex "Turtle" |
|---|---|---|
| Price | $250–$500 | $500–$1,000 |
| Case Size | 56.9 × 53.4 × 14.8mm | 45mm |
| Movement | Tough Solar (Solar Quartz), Radio-Controlled | Automatic Caliber 4R36 |
| Caliber Type | Tough Solar Quartz, Multi-Band 6 | In-House Automatic Manufacture |
| Power Reserve | Tough Solar (Rechargeable) | 41 Hours |
| Water Resistance | 200m (20 ATM) | 200m (20 ATM) Diver |
| Crystal | Mineral Glass | Sapphire Crystal |
| Case Material | Resin / Stainless Steel, Titanium Bracelet | Stainless Steel |
| Origin | Casio (Japan) | Made in Japan |
Category-by-Category Analysis
Design & Aesthetics
Casio's design language vs Seiko's approach
The Casio Pro Trek PRW3500T-7 features a Resin / Stainless Steel, Titanium Bracelet case at 56.9 × 53.4 × 14.8mm 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
Tough Solar (Solar Quartz), Radio-Controlled vs Automatic Caliber 4R36
The Pro Trek PRW3500T-7 runs the Tough Solar (Solar Quartz), Radio-Controlled (Tough Solar Quartz, Multi-Band 6, Tough Solar (Rechargeable) 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
56.9 × 53.4 × 14.8mm vs 45mm — different wrist presence
At 56.9 × 53.4 × 14.8mm, the Pro Trek PRW3500T-7 has a bolder wrist presence 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 Pro Trek PRW3500T-7 sits at $250–$500 and the Seiko Prospex "Turtle" at $500–$1,000. On the specs that outlast any price: the Pro Trek PRW3500T-7 uses Mineral Glass with Tough Solar (Rechargeable), 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 Pro Trek PRW3500T-7 is rated to 200m (20 ATM) while the Prospex "Turtle" handles 200m (20 ATM) Diver. Both offer identical water resistance ratings.
Our Verdict
Casio
Pro Trek PRW3500T-7
Choose the Casio Pro Trek PRW3500T-7 if you prioritize Tough Solar Quartz, Multi-Band 6 engineering, Casio (Japan) craftsmanship, and 200m (20 ATM) water resistance. At $250–$500, it delivers Tough Solar (Solar Quartz), Radio-Controlled with Tough Solar (Rechargeable) 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 Pro Trek PRW3500T-7 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.