What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
iTechGuides is reader-supported. When you buy through links on our site, we may earn an affiliate commission. As an Amazon Associate I earn from qualifying purchases. Learn more
Choose a G-SHOCK by checking the exact model’s features, then comparing its timekeeping and power options, stated water resistance, and full case measurements. These specifications vary across the lineup—even within a series—so a family name alone is not enough to confirm what a watch offers.
Start with the exact model number
G-SHOCK families include models with different functions and dimensions. For example, Casio lists Bluetooth smartphone link and Tough Solar on the GA-B2100-1A1, while its 2100-series chart also shows options without Bluetooth or solar in the basic grouping. Check the specifications for the precise model and regional variant you are considering rather than assuming features carry across a series.
Decide whether connected timekeeping is useful
On the GA-B2100-1A1, Casio lists Bluetooth smartphone link and automatic time adjustment, along with connected functions such as world time, reminders, and phone finder. These can be useful if you want phone-assisted settings or those additional functions; Bluetooth is not essential to choosing a G-SHOCK.
The Tool Desk
Outbyte Driver Updater FREEFix the driver behind crashes, sound loss and screen glitchesFind Drivers →Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →Timekeeping options differ by model. Some use Bluetooth adjustment, some offer radio-wave calibration, and some may have neither. Compare the exact listing rather than treating one method as standard across the range.
#1 Best Overall
- Metal-clad daring meets sophisticated gleam in this Casio G-Shock that delivers Smartphone Link via Bluetooth(R) and Tough Solar charging system, all in a meticulously finished metal design with iconic octagonal bezel
- This model features a blue metallic vapor deposition dial that is complemented by a black band made of environmentally responsible bio-based resin
Choose the power option that suits you
Casio describes Tough Solar as a system in which solar cells provide energy and excess energy is stored in a rechargeable battery. In Casio’s words, “Using solar technology, solar cells provide the watch with environmentally friendly energy, while excess solar energy is stored in a rechargeable battery.” (G-SHOCK/CASIO technology.)
If reducing reliance on conventional battery replacement matters to you, look for Tough Solar on the specific model page. Do not infer solar charging from the G-SHOCK name or series alone.
Rank #2
- Upgrade the retro look you love with the octagonal Casio G-Shock GA-2100 line, which inherits the design concept of the very first G-Shock, but now with Smartphone Link and Tough Solar power
- Bold in design, this model features a black carbon fiber-reinforced interior case and matching black resin band
Read water resistance as a model specification
Casio lists 20-bar/200-meter water resistance for both the GA-B2100-1A1 and GW-BX5600-1A1. Treat the figure as the published rating for those models. It does not, by itself, establish a guarantee for a particular activity or a dive certification. Check the exact watch’s specifications and the manufacturer’s guidance for the use you have in mind.
Compare dimensions and weight for fit
Case width alone does not tell you how a watch will fit. Compare length, width, thickness, and weight, then try it on if possible. The examples below use published specifications; the GMA-S2100 dimensions are from Casio India’s regional chart, so confirm local naming and availability.
Rank #3
- Bold, dynamic, electric - Tap into the energy of a G-SHOCK in striking black and electro green
- Featuring an LCD printed with touches of electro green, set against a bezel, band, and dial in G-SHOCK black, this is a fearless visual design that impresses and electrifies
- Case size (L? W? H): 48.5 ? 45.4 ? 11.9 mmCase and bezel material: Carbon / Bio-based resin Band: Bio-based resin bandConstruction: Shock Resistant; Carbon Core Guard structureWater resistance: 200-meter water resistanceTime adjustment - Bluetooth: Connects to a smartphone and automatically adjusts the timePower supply and battery life: Tough Solar (Solar powered)Smartphone Link feature: Mobile link (Wireless linking using Bluetooth(R))App connectivity feature: Auto time adjustment; Easy watch
| Model | Listed features | Dimensions | Weight |
|---|---|---|---|
| GA-B2100-1A1 | Bluetooth smartphone link, Tough Solar, 20-bar water resistance | 48.5 × 45.4 × 11.9 mm | 52 g |
| GW-BX5600-1A1 | Bluetooth, Tough Solar, radio-wave calibration, 20-bar water resistance | 49.1 × 44.1 × 13.4 mm | 51 g |
| GMA-S2100 series option | Smaller 2100-series choice; the cited basic grouping lists no Bluetooth or solar and 200-meter water resistance | 46.2 × 42.9 × 11.2 mm | 41 g |
The GA-B2100-1A1 is an analog-digital 2100-style example that combines Bluetooth and solar. The GW-BX5600-1A1 is a square digital option that combines Bluetooth, solar, and radio-wave calibration. The smaller GMA-S2100 option illustrates a different priority: a more compact listed size, without the Bluetooth or solar features shown for those two examples.
Quick Recap
Best Value
- Smartphone Link
- Tough Solar
- Multiband6
- 20 Bar Water Resistant
- Japan Imported
Rank #4
- Smartphone Link Functions; Battery Level Indicator; New Layer Guard Structure; Tough Solar; Dual Dial World Time; Chronograph
- 200 Meter Water Resistance; Shock Resistance; Neobrite; Bluetooth Capability
- Quartz Movement
- Case Diameter: 53.8mm
- Water resistant 200m (660ft): in general, suitable for professional marine activity and serious surface water sports, but not diving
Make the shortlist against your priorities
- Want phone-linked functions? Confirm Bluetooth and the specific functions listed for the model.
- Prefer solar power? Check for Tough Solar in that exact variant’s specification.
- Need a particular timekeeping method? Compare Bluetooth adjustment and radio-wave calibration model by model.
- Have a water-use requirement? Verify the model’s published rating and manufacturer guidance for your intended activity.
- Prioritize fit? Compare all three case dimensions and weight, and try the watch on when practical.
- Prefer a certain look? Decide between formats such as the analog-digital 2100 style and a square digital design.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
