Casio G-Shock GA-B2100 CasiOak vs OLEVS Moon Phase Dress Watch
Casio's diver meets OLEVS's dress watch
Quick Verdict
The Casio G-Shock GA-B2100 CasiOak ($100–$150) and OLEVS Moon Phase Dress Watch ($100–$150) are closely matched timepieces at similar price points. The G-Shock GA-B2100 CasiOak emphasizes Casio Quartz (Solar-Powered) engineering while the Moon Phase Dress Watch focuses on OLEVS craftsmanship.
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Specifications Compared
| Feature | Casio G-Shock GA-B2100 CasiOak | OLEVS Moon Phase Dress Watch |
|---|---|---|
| Price | $100–$150 | $100–$150 |
| Case Size | 45.4mm (48.5mm lug-to-lug, 11.9mm thick) | — |
| Movement | Quartz Module 5689 (Tough Solar + Bluetooth) | Quartz |
| Caliber Type | Casio Quartz (Solar-Powered) | Quartz (Battery) |
| Power Reserve | About 7 months on a full charge without light; about 18 months in power-saving (Casio) | — |
| Water Resistance | 200m (20 ATM) | — |
| Crystal | Mineral Glass | — |
| Case Material | Carbon Core Guard Resin | Stainless Steel |
| Origin | Made in Japan | OLEVS |
Category-by-Category Analysis
Design & Aesthetics
Casio's design language vs OLEVS's approach
The Casio G-Shock GA-B2100 CasiOak features a Carbon Core Guard Resin case at 45.4mm (48.5mm lug-to-lug, 11.9mm thick) with Mineral Glass protection. The OLEVS Moon Phase Dress Watch offers Stainless Steel construction at mid-size with crystal. Both represent their brand's distinct design philosophy and heritage.
Movement & Performance
Quartz Module 5689 (Tough Solar + Bluetooth) vs Quartz
The G-Shock GA-B2100 CasiOak runs the Quartz Module 5689 (Tough Solar + Bluetooth) (Casio Quartz (Solar-Powered), About 7 months on a full charge without light; about 18 months in power-saving (Casio) power reserve) at standard frequency. The Moon Phase Dress Watch uses the Quartz (Quartz (Battery), standard reserve) at standard. The G-Shock GA-B2100 CasiOak edges ahead on power reserve.
Wearability & Fit
45.4mm (48.5mm lug-to-lug, 11.9mm thick) vs mid-size — different wrist presence
At 45.4mm (48.5mm lug-to-lug, 11.9mm thick), the G-Shock GA-B2100 CasiOak has a bolder wrist presence compared to the Moon Phase Dress Watch at 40mm. Water resistance differs: 200m (20 ATM) vs 50m.
Value & Cost of Ownership
Same tier — different value propositions
The Casio G-Shock GA-B2100 CasiOak sits at $100–$150 and the OLEVS Moon Phase Dress Watch at $100–$150. On the specs that outlast any price: the G-Shock GA-B2100 CasiOak uses Mineral Glass with About 7 months on a full charge without light; about 18 months in power-saving (Casio), against a hardened crystal and a standard reserve on the Moon Phase Dress Watch. Service intervals are typically 5-7 years for both.
Water Resistance
200m (20 ATM) vs 50m
The G-Shock GA-B2100 CasiOak is rated to 200m (20 ATM) while the Moon Phase Dress Watch handles 50m. The G-Shock GA-B2100 CasiOak is better suited for water activities.
Our Verdict
Casio
G-Shock GA-B2100 CasiOak
Choose the Casio G-Shock GA-B2100 CasiOak if you prioritize Casio Quartz (Solar-Powered) engineering, Made in Japan craftsmanship, and 200m (20 ATM) water resistance. At $100–$150, it delivers Quartz Module 5689 (Tough Solar + Bluetooth) with About 7 months on a full charge without light; about 18 months in power-saving (Casio) power reserve.
Check Price on AmazonOLEVS
Moon Phase Dress Watch
Choose the OLEVS Moon Phase Dress Watch if you value Quartz (Battery) technology, OLEVS heritage, and comfortable proportions. At $100–$150, the Quartz with ample power reserve makes it a compelling choice.
Check Price on AmazonThe Bottom Line
The Casio G-Shock GA-B2100 CasiOak and OLEVS Moon Phase Dress Watch represent two distinct approaches to fine watchmaking — the Casio bringing Made in Japan tradition while OLEVS delivers OLEVS engineering.
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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.