






Casio G-Shock Octagon Quartz Black Dial Resin Strap Men's Watch GA-2100-1A3ER
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Casio G-Shock Octagon Series ‘CasiOak’ Quartz Grey Dial Grey Silicone Strap Men's Watch GA-2100-1A3ER
The Casio G-Shock GA-2100-1A3ER, part of the popular Octagon Series and affectionately called the "CasiOak," combines G-Shock's legendary toughness with a modern, minimalist design. Featuring an octagonal bezel, the GA-2100-1A3ER offers both durability and sleek, urban style. Whether you're out in nature or enjoying a day in the city, this watch provides the perfect balance of rugged performance and stylish appeal.
Design & Features
Dial & Display
Dial Color: Grey with Subtle Black Accents – A clean and modern look with a touch of sophistication.
Display Type: Analog-Digital Hybrid – Combining the precision of analog hands with the functionality of digital readouts.
Case & Build
Case Diameter: 45mm – A bold presence that remains comfortable on most wrists.
Case Thickness: 11mm – Slim enough for everyday wear, yet rugged enough to take on any adventure.
Strap & Comfort
Strap Material: Grey Resin – Flexible, water-resistant, and durable for a comfortable fit throughout the day.
Clasp: Buckle Closure – Easy to adjust for a secure and personalized fit.
Movement & Performance
Movement: Quartz (Module 5611) – Reliable and low-maintenance, offering precision timekeeping.
Water Resistance: 200 meters (20 ATM) – Suitable for swimming, snorkeling, and professional marine activities.
Specifications
Brand: Casio G-Shock
Series: Octagon / CasiOak
Model: GA-2100-1A3ER
Movement: Quartz (Module 5611)
Case Material: Carbon-Resin
Case Dimensions: 45mm
- Case Thickness: 11mm
Dial Color: Grey
Crystal: Mineral Glass
Strap Material: Resin
Water Resistance: 200m (20 ATM)
Key Features
Octagonal Bezel Design – Stylish and bold, with a nod to luxury sports watches.
Double LED Backlight – Easy readability in low-light conditions, ensuring clarity at all times.
World Time & Stopwatch – Great for international travelers and those who require precision timing.
200m Water Resistance – Ready for water-based activities, including swimming and snorkeling.
Who Is It For?
Fashion-Forward Watch Enthusiasts – Ideal for those who appreciate a blend of modern design with the toughness of G-Shock.
Outdoor Adventurers – Built to handle rugged environments, perfect for hiking, camping, or sports.
G-Shock Fans & Collectors – A must-have model for collectors, offering a new take on the beloved G-Shock aesthetic.
Active Lifestyles – Lightweight and durable, perfect for people on the move.
Everyday Wearers – With its stylish design and robust features, it's great for casual wear or more rugged conditions.
Final Thoughts
The Casio G-Shock GA-2100-1A3ER “CasiOak” redefines rugged luxury, blending G-Shock's durability with a refined and modern aesthetic. Its octagonal bezel, carbon-resin case, and feature-rich functionality make it a standout choice for those looking for a reliable, stylish, and high-performance timepiece. Whether you're out in nature or making a statement in the city, the GA-2100-1A3ER is the ultimate companion for both style and performance.
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UK Delivery
| Selling Price | Royal Mail 48 (Tracked) |
Royal Mail 24 (Tracked & Signed) |
Special Delivery Next Day (Mon – Fri) |
Special Sunday Delivery (Before Sat 12pm) |
Royal Mail Special Delivery by 1pm |
|---|---|---|---|---|---|
| £0 to £99.99 | FREE | £4.99 | £7.99 | £7.99 | £9.99 |
| £100 to £499.99 | N/A | FREE | £7.99 | £7.99 | £9.99 |
| £500 or more | N/A | N/A | FREE | £7.99 | £9.99 |
We know your order is important to you, so we use Royal Mail’s tracked delivery service on all UK orders.
We also offer Royal Mail Special Delivery service, which for an additional fee offers guaranteed delivery the next day before 1pm.
*Royal Mail Tracked 24 and Royal Mail Tracked 48 services are 98% accurate but not guaranteed.
Orders placed before 5pm (Monday–Friday) are dispatched the same day. Orders placed on Saturday or Sunday are dispatched the following Monday.
International Delivery
We are pleased to offer worldwide shipping. For accurate shipping rates, please add the item to your basket. Once you enter your shipping address, you will be offered all available options.
For the EU, EEA, and the rest of the world, the total price shown at checkout includes only the outbound Royal Mail / DHL shipping cost. You will be contacted by Royal Mail / DHL regarding duties and taxes. If you refuse the parcel and do not pay the required customs or duties, the outbound shipping cost will be deducted from your refund.
On average, delivery to the EU takes 3–5 working days, and delivery to the rest of the world takes 5–7 working days.
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Frequently Asked Questions
Yes — we are an Authorised Dealer for every brand we sell. All watches come with an official box, papers, and a full manufacturer’s warranty.
Every watch includes a manufacturer warranty. You’ll find more warranty info listed in the product description.
Orders placed before 5pm (Mon–Fri) are dispatched the same day. Order before 12pm on Sat for same-day dispatch. Free UK delivery is available on all orders, and tracking details are provided once shipped.
Yes — you have 30 days from delivery to return or exchange your item, provided it’s unused and in its original packaging.


