Casio F-91W vs Frederique Constant Slimline Moonphase Manufacture
Casio's timepiece meets Frederique Constant's dress watch
Quick Verdict
The Casio F-91W (Under $50) offers Casio Digital Quartz (Battery) precision in the tier below the Frederique Constant Slimline Moonphase Manufacture ($2,500–$5,000). The F-91W measures 35mm and is rated 30m (Splash Resistant). The Slimline Moonphase Manufacture counters with Swiss Made craftsmanship and 30m (3 ATM) water resistance. Both are exceptional watches for their respective tiers.
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Specifications Compared
| Feature | Casio F-91W | Frederique Constant Slimline Moonphase Manufacture |
|---|---|---|
| Price | Under $50 | $2,500–$5,000 |
| Case Size | 35mm | 42mm |
| Movement | Quartz Module 593 | Automatic FC-705 (In-House) |
| Caliber Type | Casio Digital Quartz (Battery) | In-House Automatic Manufacture |
| Power Reserve | 7-Year Battery | 42 Hours |
| Water Resistance | 30m (Splash Resistant) | 30m (3 ATM) |
| Crystal | Acrylic | Convex Sapphire |
| Case Material | Resin | Stainless Steel |
| Origin | Casio (Japan) | Swiss Made |
Category-by-Category Analysis
Design & Aesthetics
Casio's design language vs Frederique Constant's approach
The Casio F-91W features a Resin case at 35mm with Acrylic protection. The Frederique Constant Slimline Moonphase Manufacture offers Stainless Steel construction at 42mm with Convex Sapphire. Both represent their brand's distinct design philosophy and heritage.
Movement & Performance
Quartz Module 593 vs Automatic FC-705 (In-House)
The F-91W runs the Quartz Module 593 (Casio Digital Quartz (Battery), 7-Year Battery power reserve) at standard frequency. The Slimline Moonphase Manufacture uses the Automatic FC-705 (In-House) (In-House Automatic Manufacture, 42 Hours reserve) at 28,800 vph (4 Hz). The Slimline Moonphase Manufacture offers a longer power reserve.
Wearability & Fit
35mm vs 42mm — different wrist presence
At 35mm, the F-91W wears more compactly on smaller wrists compared to the Slimline Moonphase Manufacture at 42mm. Water resistance differs: 30m (Splash Resistant) vs 30m (3 ATM).
Value & Cost of Ownership
Casio sits in the lower tier
The Casio F-91W sits at Under $50 and the Frederique Constant Slimline Moonphase Manufacture at $2,500–$5,000. On the specs that outlast any price: the F-91W uses Acrylic with 7-Year Battery, against Convex Sapphire and 42 Hours on the Slimline Moonphase Manufacture. Service intervals are typically 5-7 years for both.
Water Resistance
30m (Splash Resistant) vs 30m (3 ATM)
The F-91W is rated to 30m (Splash Resistant) while the Slimline Moonphase Manufacture handles 30m (3 ATM). Both offer identical water resistance ratings.
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 AmazonFrederique Constant
Slimline Moonphase Manufacture
Choose the Frederique Constant Slimline Moonphase Manufacture if you value In-House Automatic Manufacture technology, Swiss Made heritage, and 42mm proportions. At $2,500–$5,000, the Automatic FC-705 (In-House) with 42 Hours power reserve makes it a compelling choice.
Check Price on AmazonThe Bottom Line
The Casio F-91W and Frederique Constant Slimline Moonphase Manufacture represent two distinct approaches to fine watchmaking — the Casio bringing Casio (Japan) tradition while Frederique Constant delivers Swiss Made 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.