Citizen Promaster Air Nighthawk vs Casio G-Shock GA-B2100 CasiOak
Two divers compared — ~$349 vs ~$144
Quick Verdict
The Casio G-Shock GA-B2100 CasiOak (~$144) delivers Casio Quartz (Solar-Powered) technology at $205 less than the Citizen Promaster Air Nighthawk (~$349). The Promaster Air Nighthawk justifies its premium with Citizen (Japan) heritage and Eco-Drive Caliber B877. Both represent excellent choices in the diver category.
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Specifications Compared
| Feature | Citizen Promaster Air Nighthawk | Casio G-Shock GA-B2100 CasiOak |
|---|---|---|
| Price | ~$349 | ~$144 |
| Case Size | 42mm | 44.4mm |
| Movement | Eco-Drive Caliber B877 | Quartz Module 5611 (Tough Solar + Bluetooth) |
| Caliber Type | Eco-Drive Solar Quartz (No Battery Change) | Casio Quartz (Solar-Powered) |
| Power Reserve | 6 Months (Solar, Full Charge) | — |
| Water Resistance | 200m (20 ATM) | 200m (20 ATM) |
| Crystal | Mineral Glass | Mineral Glass |
| Case Material | Stainless Steel | Carbon Core Guard Resin |
| Origin | Citizen (Japan) | Made in Japan |
Category-by-Category Analysis
Design & Aesthetics
Citizen's design language vs Casio's approach
Movement & Performance
Eco-Drive Caliber B877 vs Quartz Module 5611 (Tough Solar + Bluetooth)
Wearability & Fit
42mm vs 44.4mm — different wrist presence
Value & Cost of Ownership
Casio is $205 more affordable
Water Resistance
200m (20 ATM) vs 200m (20 ATM)
Our Verdict
Citizen
Promaster Air Nighthawk
Choose the Citizen Promaster Air Nighthawk if you prioritize Eco-Drive Solar Quartz (No Battery Change) engineering, Citizen (Japan) craftsmanship, and 200m (20 ATM) water resistance. At ~$349, it delivers Eco-Drive Caliber B877 with 6 Months (Solar, Full Charge) power reserve.
Check Price on AmazonCasio
G-Shock GA-B2100 CasiOak
Choose the Casio G-Shock GA-B2100 CasiOak if you value Casio Quartz (Solar-Powered) technology, Made in Japan heritage, and 44.4mm proportions. At ~$144, the Quartz Module 5611 (Tough Solar + Bluetooth) with ample power reserve makes it a compelling choice.
Check Price on AmazonThe Bottom Line
The Citizen Promaster Air Nighthawk and Casio G-Shock GA-B2100 CasiOak represent two distinct approaches to the diver category — the Citizen bringing Citizen (Japan) tradition while Casio delivers Made in Japan engineering.
Frequently Asked Questions
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