Head-to-Head Comparison

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.

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Casio Pro Trek PRW-B1000-1

Casio

Pro Trek PRW-B1000-1

$500–$1,000

Casio G-Shock GA-B2100 CasiOak

Casio

G-Shock GA-B2100 CasiOak

$100–$150

Specifications Compared

FeatureCasio Pro Trek PRW-B1000-1Casio G-Shock GA-B2100 CasiOak
Price$500–$1,000$100–$150
Case Size50.8 × 45.8 × 14.9mm45.4mm (48.5mm lug-to-lug, 11.9mm thick)
MovementTough Solar (Solar Quartz), Radio-ControlledQuartz Module 5689 (Tough Solar + Bluetooth)
Caliber TypeTough Solar Quartz, Multi-Band 6 + BluetoothCasio Quartz (Solar-Powered)
Power ReserveTough Solar (Rechargeable)About 7 months on a full charge without light; about 18 months in power-saving (Casio)
Water Resistance100m (10 ATM)200m (20 ATM)
CrystalSapphire with Anti-Reflective CoatingMineral Glass
Case MaterialBio-Based Resin / Stainless SteelCarbon Core Guard Resin
OriginCasio (Japan)Made in Japan

Category-by-Category Analysis

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Design & Aesthetics

Edge: Draw

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

Edge: Casio

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.

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Wearability & Fit

Edge: Casio

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).

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Value & Cost of Ownership

Edge: Casio

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.

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Water Resistance

Edge: Casio

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.

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Casio

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.

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The 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

Neither is objectively better — they serve different preferences. The Casio Pro Trek PRW-B1000-1 ($500–$1,000) offers Tough Solar (Solar Quartz), Radio-Controlled with Tough Solar (Rechargeable) power reserve, while the Casio G-Shock GA-B2100 CasiOak ($100–$150) features Quartz Module 5689 (Tough Solar + Bluetooth) with 200m (20 ATM) water resistance. Choose based on your priorities: Casio (Japan) craftsmanship vs Made in Japan engineering.
The Casio G-Shock GA-B2100 CasiOak offers better upfront value, sitting a tier lower at $100–$150. However, the Casio Pro Trek PRW-B1000-1 may justify its premium with superior finishing, heritage, or resale value.
Both are suitable for daily wear. The Pro Trek PRW-B1000-1 at 50.8 × 45.8 × 14.9mm with 100m (10 ATM) water resistance handles everyday situations. The G-Shock GA-B2100 CasiOak at 45.4mm (48.5mm lug-to-lug, 11.9mm thick) with 200m (20 ATM) is similarly capable. The Pro Trek PRW-B1000-1 uses Sapphire with Anti-Reflective Coating while the G-Shock GA-B2100 CasiOak uses Mineral Glass. Sapphire resists scratches noticeably better than mineral glass.

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.