





Casio G-Shock Octagon Quartz Black Dial Resin Strap Men's Watch GA-2100-1A3ER
CYBER WEEK DEAL
Official UK Authorised Retailer
Full Manufacturer Warranty
Free Delivery
Extended Christmas Returns Until 15th Jan 2026
Customer Service & Technical Support
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CYBER WEEK DEAL
CYBER WEEK DEAL
The Casio G-Shock GA-2100-1A3 combines rugged durability with sleek urban style, a watch built for everyday wear, sport, and adventure without sacrificing contemporary design. Its octagonal carbon-resin case paired with a resin strap gives the watch a bold yet streamlined profile, while neon-accent details on the hands and dial add a fresh, modern flair.
Tough Build & Reliable Protection
Built with G-Shock’s Carbon Core Guard construction, the GA-2100-1A3 is shock-resistant and designed to withstand rough handling, making it ideal for travel, sports, outdoor adventures or simply everyday urban life. It also offers 200 metres (20 bar) water resistance, so it’s ready for swimming or heavy rain without worry.
Feature-Rich Quartz Movement & Everyday Utility
Under the hood, the GA-2100-1A3 runs on a quartz analogue-digital combination movement, offering a suite of useful functions: a 1/100-second stopwatch, countdown timer, 5 daily alarms, full auto-calendar, world time (31 time zones), dual LED illumination (both for the analogue face and digital display), and a 12/24-hour format option. The analogue hands are coated with phosphorescent paint, ensuring visibility in the dark.
Slim Profile & Everyday Wearability
Despite being a G-Shock, the GA-2100-1A3 is notably slim: the case measures roughly 48.5 × 45.4 × 11.8mm, and the watch weighs about 51g. Its relatively low thickness and lightweight build make it comfortable for daily wear, whether under a jacket, during active use, or casual outfits.
A Stylish, Functional All-Rounder
The GA-2100-1A3 doesn’t hide its toughness; it also expresses a bold, modern aesthetic. It works as a dependable sports watch, a robust outdoor companion, or a stylish urban timepiece. For someone wanting a watch that balances resilience, versatility, and contemporary style, this G-Shock hits the mark.
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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 Shipping & Duties (Delivered At Place – DAP)
We’re pleased to offer worldwide delivery with fully tracked and insured shipping.
How international orders work
All international orders are shipped on DAP (Delivered At Place) terms. This means:
- The price you pay at checkout covers your goods and international shipping only.
- WatchNation does not collect or charge any overseas sales tax, import VAT, or customs tariffs (duties).
- When your order reaches your country, local customs authorities may apply:
- Import VAT (value-added tax),
- Tariffs or customs duties (import taxes based on product category and value), and
- Handling or clearance fees from the courier.
These charges are set by your country’s customs authority and are payable by you before delivery.
You’ll be contacted directly by DHL with a secure link to pay any applicable charges. Once cleared, your parcel will be released and delivered promptly.
Estimated delivery times (after dispatch)
- European Union: approximately 2–5 working days
- Rest of World: approximately 5–7 working days
Customs processing times vary by country and may extend delivery slightly.
If import charges, tariffs, or duties are not paid
If local charges are unpaid or delivery is refused, the shipment will be returned to us. In this case, we will refund your order minus the outbound shipping cost and any return or customs fees billed to us by the carrier.
Estimating import costs
Import VAT and duty rates vary by country. You can check estimated import taxes and tariffs by contacting your local customs authority or using your government’s online import calculator.
More about delivery...

Need help?
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.



