Head-to-Head Comparison

Casio F-91W vs Orient Kamasu Automatic Diver

Casio's timepiece meets Orient's diver

Quick Verdict

The Casio F-91W (Under $50) offers Casio Digital Quartz (Battery) precision in the tier below the Orient Kamasu Automatic Diver ($250–$500). The F-91W measures 35mm and is rated 30m (Splash Resistant). The Kamasu Automatic Diver counters with Made in Japan craftsmanship and 200m (20 ATM) water resistance. Both are exceptional watches for their respective tiers.

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Casio F-91W

Casio

F-91W

Under $50

Orient Kamasu Automatic Diver

Orient

Kamasu Automatic Diver

$250–$500

Specifications Compared

FeatureCasio F-91WOrient Kamasu Automatic Diver
PriceUnder $50$250–$500
Case Size35mm41.8mm
MovementQuartz Module 593Automatic Caliber F6922
Caliber TypeCasio Digital Quartz (Battery)Orient In-House Automatic
Power Reserve7-Year Battery40 Hours
Water Resistance30m (Splash Resistant)200m (20 ATM)
CrystalAcrylicSapphire Crystal
Case MaterialResinStainless Steel
OriginCasio (Japan)Made in Japan

Category-by-Category Analysis

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Design & Aesthetics

Edge: Draw

Casio's design language vs Orient's approach

The Casio F-91W features a Resin case at 35mm with Acrylic protection. The Orient Kamasu Automatic Diver offers Stainless Steel construction at 41.8mm with Sapphire Crystal. Both represent their brand's distinct design philosophy and heritage.

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Movement & Performance

Edge: Orient

Quartz Module 593 vs Automatic Caliber F6922

The F-91W runs the Quartz Module 593 (Casio Digital Quartz (Battery), 7-Year Battery power reserve) at standard frequency. The Kamasu Automatic Diver uses the Automatic Caliber F6922 (Orient In-House Automatic, 40 Hours reserve) at 21,600 vph (3 Hz). The Kamasu Automatic Diver offers a longer power reserve.

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Wearability & Fit

Edge: Casio

35mm vs 41.8mm — different wrist presence

At 35mm, the F-91W wears more compactly on smaller wrists compared to the Kamasu Automatic Diver at 41.8mm. Water resistance differs: 30m (Splash Resistant) vs 200m (20 ATM).

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Value & Cost of Ownership

Edge: Casio

Casio sits in the lower tier

The Casio F-91W sits at Under $50 and the Orient Kamasu Automatic Diver at $250–$500. On the specs that outlast any price: the F-91W uses Acrylic with 7-Year Battery, against Sapphire Crystal and 40 Hours on the Kamasu Automatic Diver. Service intervals are typically 5-7 years for both.

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Water Resistance

Edge: Orient

30m (Splash Resistant) vs 200m (20 ATM)

The F-91W is rated to 30m (Splash Resistant) while the Kamasu Automatic Diver handles 200m (20 ATM). The Kamasu Automatic Diver 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.

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Orient

Kamasu Automatic Diver

Choose the Orient Kamasu Automatic Diver if you value Orient In-House Automatic technology, Made in Japan heritage, and 41.8mm proportions. At $250–$500, the Automatic Caliber F6922 with 40 Hours power reserve makes it a compelling choice.

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The Bottom Line

The Casio F-91W and Orient Kamasu Automatic Diver represent two distinct approaches to fine watchmaking — the Casio bringing Casio (Japan) tradition while Orient delivers Made in Japan engineering.

Frequently Asked Questions

Neither is objectively better — they serve different preferences. The Casio F-91W (Under $50) offers Quartz Module 593 with 7-Year Battery power reserve, while the Orient Kamasu Automatic Diver ($250–$500) features Automatic Caliber F6922 with 200m (20 ATM) water resistance. Choose based on your priorities: Casio (Japan) craftsmanship vs Made in Japan engineering.
The Casio F-91W offers better upfront value, sitting a tier lower at Under $50. However, the Orient Kamasu Automatic Diver may justify its premium with superior finishing, heritage, or resale value.
Both are suitable for daily wear. The F-91W at 35mm with 30m (Splash Resistant) water resistance handles everyday situations. The Kamasu Automatic Diver at 41.8mm with 200m (20 ATM) is similarly capable. The F-91W uses Acrylic while the Kamasu Automatic Diver uses Sapphire Crystal. Sapphire resists scratches noticeably better than acrylic.

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.