<p class="font_8">**Casio G-Shock CasiOak Model GM2100CB-1A Review by A.I. WatchMetrics**

### Watch Summary:
The Casio G-Shock CasiOak GM2100CB-1A is a robust and versatile timepiece, classified under the Sport/Active style category. Known for its distinctive octagonal bezel, this model combines the iconic G-Shock durability with a sleek, modern design. It is intended for individuals who require a reliable watch for outdoor activities and everyday wear, offering both style and functionality. The watch features a quartz movement, ensuring precise timekeeping, and is powered by a battery with an approximate lifespan of three years. Its standout features include shock resistance, 200-meter water resistance, and a range of practical functions such as a stopwatch, countdown timer, and world time.

### Overall Watch Rating: 7.0/10.0

- **Functions Metric (9.0/10.0)**
- The GM2100CB-1A excels in functionality with its 200-meter water resistance, shock resistance, and world time feature, making it ideal for active users. The inclusion of a stopwatch and countdown timer further enhances its utility.

- **Versatility Metric (8.5/10.0)**
- This watch is highly versatile, suitable for both casual and active settings. Its durable build and practical features make it a reliable choice for various environments.

- **Movement Metric (8.0/10.0)**
- The quartz movement ensures accurate timekeeping and low maintenance, which is typical for G-Shock models. While not as complex as mechanical movements, it offers reliability and precision.

- **Material Metric (7.5/10.0)**
- The watch features a stainless steel bezel with a resin band, providing a balance of durability and comfort. The materials are standard for G-Shock models, offering good resistance to wear and tear.

- **Dials &amp; Design Metric (7.0/10.0)**
- The design is modern and distinctive, with a clear and legible dial. The octagonal bezel adds a unique touch, although the design remains consistent with other G-Shock models.

- **Brand Metric (6.5/10.0)**
- Casio is well-regarded for its durable and affordable watches, particularly the G-Shock line. While not a luxury brand, it has a strong reputation for reliability and innovation in the consumer segment.

- **Rarity Metric (6.0/10.0)**
- The GM2100CB-1A is widely available, typical for G-Shock models, which are produced in large quantities. Its popularity and accessibility contribute to a lower rarity score.

- **History &amp; Innovation Metric (5.5/10.0)**
- While the G-Shock line is known for its innovation in durability and functionality, this specific model does not introduce groundbreaking features beyond the established G-Shock standards.

- **Complications Metric (5.0/10.0)**
- The watch includes basic complications such as a stopwatch and world time, which are standard for digital watches. These features are practical but not considered advanced.

### Celebrity and Historical Figures:
While no specific celebrities are known to wear the GM2100CB-1A, the G-Shock line is popular among athletes and outdoor enthusiasts for its durability and functionality. Casio G-Shock watches have been seen on the wrists of various celebrities, including musicians and actors, who appreciate their rugged design and reliability.</p>