Updated
Casio Pro Trek PRW-B1000-1 vs Casio G-Shock GA-B2100 CasiOak
Casio's timepiece meets Casio's diver
Quick Verdict
The Casio G-Shock GA-B2100 CasiOak ($100–$150) delivers Casio Quartz (Solar-Powered) technology in the tier below the Casio Pro Trek PRW-B1000-1 ($500–$1,000). The G-Shock GA-B2100 CasiOak measures 45.4mm (48.5mm lug-to-lug, 11.9mm thick) and is rated 200m (20 ATM). The Pro Trek PRW-B1000-1 justifies its premium with Casio (Japan) heritage and Tough Solar (Solar Quartz), Radio-Controlled. Both represent excellent choices in the luxury watch category.
Transparency — We earn a small commission on purchases made through our Amazon links. This doesn't affect our editorial independence.
Specifications Compared
| Feature | Casio Pro Trek PRW-B1000-1 | Casio G-Shock GA-B2100 CasiOak |
|---|---|---|
| Price | $500–$1,000 | $100–$150 |
| Case Size | 50.8 × 45.8 × 14.9mm | 45.4mm (48.5mm lug-to-lug, 11.9mm thick) |
| Movement | Tough Solar (Solar Quartz), Radio-Controlled | Quartz Module 5689 (Tough Solar + Bluetooth) |
| Caliber Type | Tough Solar Quartz, Multi-Band 6 + Bluetooth | Casio Quartz (Solar-Powered) |
| Power Reserve | Tough Solar (Rechargeable) | About 7 months on a full charge without light; about 18 months in power-saving (Casio) |
| Water Resistance | 100m (10 ATM) | 200m (20 ATM) |
| Crystal | Sapphire with Anti-Reflective Coating | Mineral Glass |
| Case Material | Bio-Based Resin / Stainless Steel | Carbon Core Guard Resin |
| Origin | Casio (Japan) | Made in Japan |
Category-by-Category Analysis
Design & Aesthetics
Casio's design language vs Casio's approach
The Casio Pro Trek PRW-B1000-1 features a Bio-Based Resin / Stainless Steel case at 50.8 × 45.8 × 14.9mm with Sapphire with Anti-Reflective Coating protection. The Casio G-Shock GA-B2100 CasiOak offers Carbon Core Guard Resin construction at 45.4mm (48.5mm lug-to-lug, 11.9mm thick) with Mineral Glass. Both represent their brand's distinct design philosophy and heritage.
Movement & Performance
Tough Solar (Solar Quartz), Radio-Controlled vs Quartz Module 5689 (Tough Solar + Bluetooth)
The Pro Trek PRW-B1000-1 runs the Tough Solar (Solar Quartz), Radio-Controlled (Tough Solar Quartz, Multi-Band 6 + Bluetooth, Tough Solar (Rechargeable) power reserve) at standard frequency. The G-Shock GA-B2100 CasiOak uses 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) reserve) at standard. The G-Shock GA-B2100 CasiOak offers a longer power reserve.
Wearability & Fit
50.8 × 45.8 × 14.9mm vs 45.4mm (48.5mm lug-to-lug, 11.9mm thick) — different wrist presence
At 50.8 × 45.8 × 14.9mm, the Pro Trek PRW-B1000-1 has a bolder wrist presence compared to the G-Shock GA-B2100 CasiOak at 45.4mm (48.5mm lug-to-lug, 11.9mm thick). Water resistance differs: 100m (10 ATM) vs 200m (20 ATM).
Value & Cost of Ownership
Casio sits in the lower tier
The Casio Pro Trek PRW-B1000-1 sits at $500–$1,000 and the Casio G-Shock GA-B2100 CasiOak at $100–$150. On the specs that outlast any price: the Pro Trek PRW-B1000-1 uses Sapphire with Anti-Reflective Coating with Tough Solar (Rechargeable), against Mineral Glass and About 7 months on a full charge without light; about 18 months in power-saving (Casio) on the G-Shock GA-B2100 CasiOak. Service intervals are typically 5-7 years for both.
Water Resistance
100m (10 ATM) vs 200m (20 ATM)
The Pro Trek PRW-B1000-1 is rated to 100m (10 ATM) while the G-Shock GA-B2100 CasiOak handles 200m (20 ATM). The G-Shock GA-B2100 CasiOak offers superior water resistance.
Our Verdict
Casio
Pro Trek PRW-B1000-1
Choose the Casio Pro Trek PRW-B1000-1 if you prioritize Tough Solar Quartz, Multi-Band 6 + Bluetooth engineering, Casio (Japan) craftsmanship, and 100m (10 ATM) water resistance. At $500–$1,000, it delivers Tough Solar (Solar Quartz), Radio-Controlled with Tough Solar (Rechargeable) 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 45.4mm (48.5mm lug-to-lug, 11.9mm thick) proportions. At $100–$150, the 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 makes it a compelling choice.
Check Price on AmazonThe Bottom Line
The Casio Pro Trek PRW-B1000-1 and Casio G-Shock GA-B2100 CasiOak represent two distinct approaches to fine watchmaking — the Casio bringing Casio (Japan) tradition while Casio delivers Made in Japan engineering.
Frequently Asked Questions
More Comparisons
Explore These Watches
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.