Casio G-Shock GA-B2100 CasiOak vs Tissot Seastar 1000 Automatic
Two divers compared — ~$144 vs ~$515
Quick Verdict
The Casio G-Shock GA-B2100 CasiOak (~$144) offers Casio Quartz (Solar-Powered) precision at $371 less than the Tissot Seastar 1000 Automatic (~$515). The Seastar 1000 Automatic counters with Swiss Made craftsmanship and 300m (30 ATM) water resistance. Both are exceptional divers for their respective price points.
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Specifications Compared
| Feature | Casio G-Shock GA-B2100 CasiOak | Tissot Seastar 1000 Automatic |
|---|---|---|
| Price | ~$144 | ~$515 |
| Case Size | 44.4mm | 40mm |
| Movement | Quartz Module 5611 (Tough Solar + Bluetooth) | Automatic Powermatic 80 (Caliber 80.111) |
| Caliber Type | Casio Quartz (Solar-Powered) | ETA/Tissot Automatic |
| Power Reserve | — | 80 Hours |
| Water Resistance | 200m (20 ATM) | 300m (30 ATM) |
| Crystal | Mineral Glass | Sapphire Crystal |
| Case Material | Carbon Core Guard Resin | Stainless Steel |
| Origin | Made in Japan | Swiss Made |
Category-by-Category Analysis
Design & Aesthetics
Casio's design language vs Tissot's approach
Movement & Performance
Quartz Module 5611 (Tough Solar + Bluetooth) vs Automatic Powermatic 80 (Caliber 80.111)
Wearability & Fit
44.4mm vs 40mm — different wrist presence
Value & Cost of Ownership
Casio is $371 more affordable
Water Resistance
200m (20 ATM) vs 300m (30 ATM)
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 ~$144, it delivers Quartz Module 5611 (Tough Solar + Bluetooth) with solid power reserve.
Check Price on AmazonTissot
Seastar 1000 Automatic
Choose the Tissot Seastar 1000 Automatic if you value ETA/Tissot Automatic technology, Swiss Made heritage, and 40mm proportions. At ~$515, the Automatic Powermatic 80 (Caliber 80.111) with 80 Hours power reserve makes it a compelling choice.
Check Price on AmazonThe Bottom Line
The Casio G-Shock GA-B2100 CasiOak and Tissot Seastar 1000 Automatic represent two distinct approaches to the diver category — the Casio bringing Made in Japan tradition while Tissot delivers Swiss Made engineering.
Frequently Asked Questions
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