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Casio Duro vs Seiko Alpinist
Same 200m rating, very different watches
Quick Verdict
The Casio Duro MDV106 ($50–$100) and the Seiko Alpinist SPB210 ($500–$1,000) are both rated to 200m. The Duro is a 44mm quartz diver with mineral glass. The Alpinist is a 39.5mm automatic explorer with a sapphire crystal, an inner compass bezel and a 70-hour reserve. Same water rating; the Alpinist is the finer watch, the Duro the cheaper one.
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Specifications Compared
| Feature | Casio Duro MDV-106B Blue | Seiko Prospex Alpinist |
|---|---|---|
| Price | $50–$100 | $500–$1,000 |
| Case Size | 44mm | 39.5mm |
| Movement | Quartz Module 2784 | Automatic Caliber 6R35 |
| Caliber Type | Casio Quartz (Battery) | In-House Automatic Manufacture |
| Power Reserve | 3-Year Battery | 70 Hours |
| Water Resistance | 200m (20 ATM) Diver | 200m (20 ATM) |
| Crystal | Mineral Glass | Sapphire with Cyclops |
| Case Material | Stainless Steel | Stainless Steel |
| Origin | Casio (Japan) | Made in Japan |
Category-by-Category Analysis
Design & Aesthetics
Diver against explorer
The Duro is a straightforward diver with an outer unidirectional bezel. The Alpinist is an explorer watch with an inner rotating compass bezel and a sunburst dial. The Alpinist dresses up more easily; the Duro is the purer tool.
Movement & Performance
Quartz against an in-house 70-hour automatic
The Duro runs Casio quartz Module 2784 on a battery rated at about three years. The Alpinist runs Seiko's in-house 6R35, a 24-jewel automatic at 21,600 vph with a 70-hour reserve. The Duro is more accurate; the Alpinist is the more interesting movement and never needs a battery.
Durability & Water Resistance
Same rating, better crystal on the Alpinist
Both are rated to 200m (20 ATM). The Duro adds a screw-down crown and caseback; the Alpinist adds a sapphire crystal with a cyclops over the date. Mineral glass on the Duro will scratch more readily than the Alpinist's sapphire.
Wearability & Fit
The Alpinist is 4.5mm smaller
The Alpinist is 39.5mm and the Duro is 44mm. That is a large gap. The Alpinist suits nearly any wrist; the Duro is best on medium to larger wrists.
Value & Cost of Ownership
The Duro is the far cheaper way to 200m
The Duro sits in the $50–$100 band and the Alpinist in $500–$1,000. If 200m is the main requirement, the Duro gets there for much less. The Alpinist earns its premium with sapphire, a 70-hour automatic and a more wearable size.
Our Verdict
Casio
Duro MDV-106B Blue
Choose the Casio Duro if you want 200m of water resistance and a real dive bezel for the least money. It is quartz, so it keeps good time and needs a battery roughly every three years.
Check Price on AmazonSeiko
Prospex Alpinist
Choose the Seiko Alpinist if you want one good automatic to wear everywhere. It matches the Duro's 200m rating, adds sapphire and a 70-hour reserve, and at 39.5mm it is the smaller and more versatile watch. The inner compass bezel is the explorer's tool rather than a dive timer.
Check Price on AmazonThe Bottom Line
The Casio Duro MDV106 and the Seiko Prospex Alpinist SPB210 are both rated to 200m water resistance, but the Alpinist adds a sapphire crystal, an in-house 6R35 automatic with a 70-hour power reserve and a smaller 39.5mm case, while the Duro is a 44mm quartz diver costing a fraction as much.
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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.