Casio G-SHOCK 2100 Dual Display Bluetooth Solar Watch (GA-B2100-1AER)

Overview

The Casio G-SHOCK GA-B2100-1A combines the iconic octagonal design of the G-SHOCK 2100 Series with advanced solar-powered technology and Bluetooth® smartphone connectivity. Building on the popularity of the original GA-2100, this upgraded analogue-digital watch introduces Tough Solar charging and Smartphone Link functionality while retaining the slim profile, lightweight construction and legendary durability that define the G-SHOCK range.

Featuring a distinctive black resin case with contrasting grey dial details, the GA-B2100-1A delivers a versatile appearance suited to professional environments, outdoor activities and everyday wear. Its Carbon Core Guard construction provides exceptional shock resistance, while 200-metre water resistance, dual LED illumination and precision timekeeping ensure dependable performance in demanding conditions. Weighing just 52 g and measuring only 11.9 mm thick, it offers impressive functionality without unnecessary bulk.

Key Features

• Iconic octagonal G-SHOCK 2100 Series design
• Tough Solar technology converts natural and artificial light into power
• Bluetooth® Smartphone Link with automatic time adjustment
• Carbon Core Guard structure for lightweight shock resistance
• 200-metre water resistance for demanding everyday and outdoor use
• Analogue-digital display with distinctive dual-layer dial
• Double LED Super Illuminator for improved visibility in darkness
• World Time covering 38 time zones, with additional cities available through the smartphone app
• 1/100-second stopwatch and 60-minute countdown timer
• Five daily alarms and hourly time signal
• Hand Shift function moves the hands to reveal the digital display
• Power Saving mode and battery level indicator
• Lightweight 52 g construction for comfortable everyday wear

Specifications

• Model: GA-B2100-1A
• Series: G-SHOCK 2100 Series
• Display: Analogue and digital
• Case Dimensions: 48.5 × 45.4 × 11.9 mm
• Weight: 52 g
• Case & Bezel Material: Carbon / resin
• Strap: Resin band
• Compatible Wrist Size: 145–215 mm
• Glass: Mineral glass
• Construction: Shock Resistant, Carbon Core Guard
• Water Resistance: 200 metres (20 bar)
• Power Source: Tough Solar rechargeable battery
• Connectivity: Bluetooth® Smartphone Link
• Compatible App: CASIO WATCHES
• Timekeeping Accuracy: ±15 seconds per month without Smartphone Link
• Battery Operating Time: Approximately 7 months after full charge without further light exposure under normal use
• Power Saving Battery Life: Approximately 18 months after full charge when stored in darkness with Power Saving enabled
• Additional Features: Neobrite luminous coating, Hand Shift and battery level indicator

Carbon Core Guard Protection

At the heart of the GA-B2100-1A is Casio's advanced Carbon Core Guard structure, which uses carbon fibre-reinforced resin to protect the watch module against shocks and impacts. This lightweight yet robust construction allows the watch to maintain a slim, comfortable profile without compromising the durability expected from G-SHOCK.

The distinctive octagonal bezel takes inspiration from the original G-SHOCK design philosophy, combining a recognisable appearance with practical protection. Its resin strap provides flexibility and comfort during prolonged wear, while the mineral glass protects the dial against everyday wear.

With 200-metre water resistance, the watch is suitable for swimming, water-based activities and demanding outdoor conditions, making it a dependable choice for users who require a versatile timepiece capable of handling both work and leisure.

Tough Solar Power

The GA-B2100-1A features Casio's Tough Solar technology, which converts natural and artificial light into electrical energy to power the watch. This eliminates the need for frequent conventional battery replacements and provides reliable operation throughout everyday use.

An integrated rechargeable battery stores energy for use in low-light conditions, delivering approximately seven months of normal operation after a full charge without additional light exposure. When Power Saving mode is enabled, the watch can operate for approximately 18 months in darkness after a full charge.

A battery level indicator makes it easy to monitor the remaining charge, while the Power Saving function automatically reduces energy consumption when the watch is left in darkness for extended periods.

Bluetooth® Smartphone Link

Bluetooth® connectivity allows the GA-B2100-1A to connect to a compatible smartphone using the CASIO WATCHES app. Once paired, the watch can automatically synchronise its time with the smartphone, helping maintain accurate timekeeping without the need for regular manual adjustment.

The Smartphone Link system also makes it easier to configure watch settings, manage alarms, select World Time locations and access additional functionality through a familiar smartphone interface.

• Automatic Time Adjustment: Synchronises the watch with a connected smartphone up to four times per day.
• Easy Watch Settings: Configure alarms, timers and other settings through the CASIO WATCHES app.
• World Time: Access approximately 300 cities through the smartphone app.
• Time & Place: Record the current time and location using the connected smartphone.
• Reminder Function: Receive reminders for up to five events configured in the app.
• Phone Finder: Activate an audible alert on a connected smartphone to help locate it.
• Home Time / World Time Switching: Conveniently swap between local and international time settings.

Watch Features & Functions

• World Time: 38 time zones covering 38 cities plus Coordinated Universal Time (UTC), with daylight saving settings and automatic summer time switching.
• Stopwatch: 1/100-second measurement for the first 60 minutes, switching to one-second measurement thereafter, with elapsed time and lap/split functions.
• Countdown Timer: Adjustable from one second to 60 minutes, with one-second measurement intervals.
• Daily Alarms: Five independent daily alarms.
• Hourly Time Signal: Optional audible signal every hour.
• Double LED Super Illuminator: Separate white LED illumination for the analogue dial and digital display, with selectable 1.5 or 3-second illumination and afterglow.
• Hand Shift: Temporarily moves the analogue hands away from the digital display for improved visibility.
• Full Auto Calendar: Automatically adjusts dates through to 2099.
• Time Format: Selectable 12 or 24-hour display.
• Date Display: Adjustable date/month display order.
• Day Display: Day of the week available in six languages.
• Button Tone: Option to enable or disable button operation sounds.
• Battery Level Indicator: Displays remaining rechargeable battery capacity.

Designed for Everyday Reliability

The GA-B2100-1A is designed for users who want a dependable, practical watch without sacrificing comfort or appearance. Its lightweight Carbon Core Guard construction, slim case and flexible resin strap make it comfortable during extended wear, whether working long shifts, travelling or spending time outdoors.

The combination of solar charging, automatic smartphone time adjustment and robust shock-resistant construction makes it particularly appealing to users who value low-maintenance equipment. Clear analogue hands, a compact digital display and dual LED illumination provide useful timekeeping information across a variety of lighting conditions.

Why Choose the Casio G-SHOCK GA-B2100-1A?

The GA-B2100-1A offers an excellent balance of classic G-SHOCK styling and modern functionality. Compared with the standard battery-powered GA-2100, it adds Tough Solar charging and Bluetooth® Smartphone Link while retaining the distinctive octagonal case, lightweight construction and exceptional shock resistance that made the original model so popular.

With 200-metre water resistance, Carbon Core Guard protection, advanced timekeeping functions and a versatile black-and-grey design, it is an excellent choice for anyone seeking a durable analogue-digital watch that performs reliably at work, outdoors and during everyday activities.

Authorised Casio Retailer

TacTree is an authorised Casio UK retailer. All Casio watches supplied are 100% genuine, brand new and sourced through approved UK distribution channels. Orders are supplied with official Casio packaging and manufacturer documentation for complete authenticity and peace of mind.