Casio F-91W vs Citizen Promaster Sea Eco-Drive Diver
Casio's timepiece meets Citizen's diver
Quick Verdict
The Casio F-91W (~$20) offers Casio Digital Quartz (Battery) precision at $270 less than the Citizen Promaster Sea Eco-Drive Diver (~$290). The Promaster Sea Eco-Drive Diver counters with Made in Japan craftsmanship and 200m (20 ATM) ISO 6425 water resistance. Both are exceptional watches for their respective price points.
Transparency — We earn a small commission on purchases made through our Amazon links. This doesn't affect our editorial independence.
Specifications Compared
| Feature | Casio F-91W | Citizen Promaster Sea Eco-Drive Diver |
|---|---|---|
| Price | ~$20 | ~$290 |
| Case Size | 35mm | 44mm |
| Movement | Quartz Module 593 | Eco-Drive Caliber E168 |
| Caliber Type | Casio Digital Quartz (Battery) | Citizen Eco-Drive (Solar Quartz) |
| Power Reserve | 7-Year Battery | — |
| Water Resistance | 30m (Splash Resistant) | 200m (20 ATM) ISO 6425 |
| Crystal | Acrylic | Mineral Crystal |
| Case Material | Resin | Stainless Steel |
| Origin | Casio (Japan) | Made in Japan |
Category-by-Category Analysis
Design & Aesthetics
Casio's design language vs Citizen's approach
Movement & Performance
Quartz Module 593 vs Eco-Drive Caliber E168
Wearability & Fit
35mm vs 44mm — different wrist presence
Value & Cost of Ownership
Casio is $270 more affordable
Water Resistance
30m (Splash Resistant) vs 200m (20 ATM) ISO 6425
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 ~$20, it delivers Quartz Module 593 with 7-Year Battery power reserve.
Check Price on AmazonCitizen
Promaster Sea Eco-Drive Diver
Choose the Citizen Promaster Sea Eco-Drive Diver if you value Citizen Eco-Drive (Solar Quartz) technology, Made in Japan heritage, and 44mm proportions. At ~$290, the Eco-Drive Caliber E168 with ample power reserve makes it a compelling choice.
Check Price on AmazonThe Bottom Line
The Casio F-91W and Citizen Promaster Sea Eco-Drive Diver represent two distinct approaches to fine watchmaking — the Casio bringing Casio (Japan) tradition while Citizen delivers Made in Japan engineering.