Casio F-91W vs Invicta Pro Diver Automatic 23681
Casio's timepiece meets Invicta's diver
Quick Verdict
The Casio F-91W (Under $50) and Invicta Pro Diver Automatic 23681 ($50–$100) are closely matched timepieces at similar price points. The F-91W emphasizes Casio Digital Quartz (Battery) engineering while the Pro Diver Automatic 23681 focuses on Invicta (Japanese movement) craftsmanship.
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Specifications Compared
| Feature | Casio F-91W | Invicta Pro Diver Automatic 23681 |
|---|---|---|
| Price | Under $50 | $50–$100 |
| Case Size | 35mm | 40mm |
| Movement | Quartz Module 593 | Automatic NH35A |
| Caliber Type | Casio Digital Quartz (Battery) | Automatic (Seiko NH35A) |
| Power Reserve | 7-Year Battery | — |
| Water Resistance | 30m (Splash Resistant) | 200m |
| Crystal | Acrylic | Mineral Glass |
| Case Material | Resin | — |
| Origin | Casio (Japan) | Invicta (Japanese movement) |
Category-by-Category Analysis
Design & Aesthetics
Casio's design language vs Invicta's approach
The Casio F-91W features a Resin case at 35mm with Acrylic protection. The Invicta Pro Diver Automatic 23681 offers steel construction at 40mm with Mineral Glass. Both represent their brand's distinct design philosophy and heritage.
Movement & Performance
Quartz Module 593 vs Automatic NH35A
The F-91W runs the Quartz Module 593 (Casio Digital Quartz (Battery), 7-Year Battery power reserve) at standard frequency. The Pro Diver Automatic 23681 uses the Automatic NH35A (Automatic (Seiko NH35A), standard reserve) at standard. The F-91W edges ahead on power reserve.
Wearability & Fit
35mm vs 40mm — different wrist presence
At 35mm, the F-91W wears more compactly on smaller wrists compared to the Pro Diver Automatic 23681 at 40mm. Water resistance differs: 30m (Splash Resistant) vs 200m.
Value & Cost of Ownership
Same tier — different value propositions
The Casio F-91W sits at Under $50 and the Invicta Pro Diver Automatic 23681 at $50–$100. On the specs that outlast any price: the F-91W uses Acrylic with 7-Year Battery, against Mineral Glass and a standard reserve on the Pro Diver Automatic 23681. Service intervals are typically 5-7 years for both.
Water Resistance
30m (Splash Resistant) vs 200m
The F-91W is rated to 30m (Splash Resistant) while the Pro Diver Automatic 23681 handles 200m. The Pro Diver Automatic 23681 offers superior water resistance.
Our Verdict
Casio
F-91W
Choose the Casio F-91W if you prioritize Casio Digital Quartz (Battery) engineering, Casio (Japan) craftsmanship, and 30m (Splash Resistant) water resistance. At Under $50, it delivers Quartz Module 593 with 7-Year Battery power reserve.
Check Price on AmazonInvicta
Pro Diver Automatic 23681
Choose the Invicta Pro Diver Automatic 23681 if you value Automatic (Seiko NH35A) technology, Invicta (Japanese movement) heritage, and 40mm proportions. At $50–$100, the Automatic NH35A with ample power reserve makes it a compelling choice.
Check Price on AmazonThe Bottom Line
The Casio F-91W and Invicta Pro Diver Automatic 23681 represent two distinct approaches to fine watchmaking — the Casio bringing Casio (Japan) tradition while Invicta delivers Invicta (Japanese movement) 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.