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Casio GA2100-1A1 (CasiOak) Specifications
| Reference | GA-2100-1A1 |
|---|---|
| Case Size | 45.4mm |
| Lug Width | 24mm |
| Lug-to-Lug | 48.5mm |
| Thickness | 11.8mm |
| Case Material | carbon core guard resin |
| Crystal | mineral glass |
| Water Resistance | 200m |
| Movement | 5611 (quartz (analog-digital)) |
| Bezel | fixed resin bezel/octagonal |
| Crown | push buttons |
| Case Back | screw-down |
| Price Range | $90-$120 |
Compatible Straps for the Casio GA2100-1A1 (CasiOak)
The GA2100-1A1 (CasiOak) uses a 24mm Lug Width and is compatible with the following strap types.
| Type | Recommended Brand | Why It Works | Price Range | Link |
|---|---|---|---|---|
| OEM resin band | JaysAndKays | Compatible with 24mm attachment | $15–$80 | |
| aftermarket resin band | Casio OEM | Compatible with 24mm attachment | $15–$80 | |
| metal conversion kit bracelet | Aliexpress metal kits | Compatible with 24mm attachment | $15–$80 | |
| NATO/ZULU (with adapter) | Barton (with adapter) | Classic look, easy to swap, fits 24mm lugs | $15–$80 | |
| rubber/silicone (with adapter) | JaysAndKays | Water-resistant, comfortable for daily wear | $15–$80 |
Replacement Parts for the Casio GA2100-1A1 (CasiOak)
| Part | Description | Compatibility Note |
|---|---|---|
| resin band | Replacement wrist band | 24mm attachment |
| resin bezel/shell | Outer ring marking | Matches fixed resin bezel/octagonal configuration |
| spring bars | Pins that hold the strap to the case | 24mm, 1.5mm diameter recommended |
| battery (SR726W) | Replacement component | Check compatibility with GA2100-1A1 (CasiOak) |
| back cover gasket | Seal that maintains water resistance | Required for 200m WR rating |
| buttons | Replacement component | Check compatibility with GA2100-1A1 (CasiOak) |
Modding the Casio GA2100-1A1 (CasiOak)
The GA2100-1A1 (CasiOak) is a popular platform for modding. Here are the most common modifications.
- metal case/bracelet conversion kit (Royal Oak style) — Upgrade to a premium aftermarket strap or metal bracelet.
- bezel swap — Swap the stock bezel insert for a ceramic, lumed, or differently colored option.
- display mod — Popular modification for the GA2100-1A1 (CasiOak).
Frequently Asked Questions
What is the CasiOak metal mod?
The CasiOak metal mod replaces the resin case and band with a stainless steel case and bracelet, giving the GA2100 a look similar to the Audemars Piguet Royal Oak. Kits range from $30-$150.
Can I use a NATO strap on the GA2100?
Not directly. The GA2100 uses an integrated resin band. You need a spring bar adapter to use a NATO strap. JaysAndKays makes popular adapter options.
Why is the GA2100 called the CasiOak?
The GA2100 earned the nickname 'CasiOak' from watch enthusiasts because its octagonal bezel design resembles the iconic Audemars Piguet Royal Oak, but at a fraction of the price.