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G-SHOCK

GRB300EC-1A

$699.00
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Whatever you’re doing, wherever you are — the G-SHOCK Master of G line has your back.

Based on GRAVITYMASTER, MUDMASTER, and MUDMAN models that deliver peak performance in punishing conditions in the air and on land, this line features a black watch case symbolising toughness, with accents in vivid emergency colours that capture the world of professionals involved in rescue efforts and other critical missions.

The organic form of the GRAVITYMASTER GR-B300EC is inspired by next-generation aircraft and rendered with a seamless exterior design. The Carbon Core Guard structure and wide 3D face deliver durability, readability, and a comfortable fit. Enjoy all the practical functions as well, including dual-time simultaneously showing the time in two cities, a flight log memory function for recording routes traveled, and more.

Basic Information
  • Band
    Bio-based resin band
  • Case and bezel material
    Bio-based Carbon / Bio-based resin / Stainless steel
  • Case size (L × W × H)
    59 × 54.7 × 15.7 mm
  • Construction
    Shock Resistant, Carbon Core Guard structure
  • Power supply and battery life
    Tough Solar (Solar powered)
  • Time adjustment
    Bluetooth: Connects to a smartphone and automatically adjusts the time
  • Water resistance
    200-metre water resistance
  • Weight
    71 g

Exterior
  • Compatible band size
    145 to 215 mm
  • Crown
    Screw Lock Crown
  • Glass
    Mineral Glass
  • Other
    Neobrite
  • Surface treatment
    Black ion plated bezel

Smartphone Link / App Connectivity Features
  • App connectivity feature
    Auto time adjustment, Easy watch setting, Approximately 300 world time cities, Flight log, Phone finder
  • Apps
    CASIO WATCHES
  • Smartphone link feature
    Mobile link (Wireless linking using Bluetooth®)

Features
  • Accuracy
    Accuracy: ±15 seconds per month (with no mobile link function)
  • Alarm / hourly time signal
    Daily alarm
  • Battery display alert
    Battery level indicator
  • Calendar
    Full auto-calendar (to year 2099)
  • Energy saving feature
    Power Saving (hands stop to save power when the watch is left in the dark)
  • Light
    LED light (Super Illuminator)
    Afterglow
  • Other features
    Date display
    Day indicator
    Regular timekeeping:
    Analog: 3 hands (hour, minute (hand moves every 10 seconds), second), 3 dials (dual time hour and minute, dual time 24-hour, day)
  • Run time
    Approx. battery operating time:
    5 months on rechargeable battery (operation period with normal use without exposure to light after charge)
    18 months on rechargeable battery (operation period when stored in total darkness with the power save function on after full charge)
  • Stopwatch
    1-second stopwatch
    Measuring capacity: 23:59'59.
    Measuring modes: Elapsed time, split time
  • Timer
    Countdown timer
    Measuring unit: 1 second
    Countdown range: 24 hours
    Countdown start time setting range: 1 minute to 24 hours (1-minute increments and 1-hour increments)
  • World time
    Dual time (Home City time swapping)
User Manual – Module 5719

Emergency colours accenting a black watch face

Vivid red, orange, and yellow hues employed by rescue teams and other professionals are featured as accent colours. Their striking contrast against the powerful solid black design ensures readability while creating a look befitting professional gear.

*Image shows the GRB300EC-1A.

Duplex LCD - MUDMAN GW-9500MEC

While providing resistance to dust, mud, and shock with its structure, this watch also incorporates radio-controlled, solar-powered functionality. The digital compass display with improved readability employs a duplex LCD for greater practical utility. Stainless steel is used for the bezel components, with black IP completing the look with an intrepid appearance.

*Second image shows the GW9500-3.

Carbon Core Guard structure, both strong and light

A carbon fibre-reinforced resin case*1 protects the module, making the most of the high degree of strength and outstanding durability delivered by the carbon material to achieve a size ensuring a comfortable fit.

*1 Due to the characteristics of carbon fibre-reinforced resin, the pattern and colour tone that appears on the surface will vary model by model.

*Image shows the GRB300EC-1A.

Mud-resistant structure to withstand use in the harshest conditions

GWG-B1000EC and GW-9500MEC

The buttons are protected by cylindrical stainless-steel parts, and the button shafts are equipped with gasket fittings to prevent contamination with mud and dust. The GWG-B1000EC features a crown with a screw-lock construction to ensure a water-tight seal.

*Image shows the GWGB1000-1A.

Triple Sensor (digital compass, barometer/altimeter, and thermometer) senses natural changes

GWG-B1000EC and GW-9500MEC

*Image shows the GW9500MEC-1.

Solar-powered timekeeping with Bluetooth® connectivity and/or radio control for enhanced accuracy and reliability

GR-B300EC: Bluetooth®
GWG-B1000EC: Bluetooth® and Multiband 6 radio control
GW-9500MEC: Multiband 6 radio control

*Image shows the GRB300EC-1A.

Feature List

  • Black icon of a watch hitting a flat surface with motion lines indicating a shock or impact.

    Shock resistant

  • Black icon of a person snorkeling with the number 20, representing a 20-bar pressure rating for water resistance.

    20 bar water resistant

  • Minimalist black icon of a person walking next to a simple clock face, representing punctuality or time management.

    Keeps yourself in time

  • Black icon of a smartwatch charging via solar energy with a battery level indicator and sun rays.

    Stable solar power

  • Black and white icon of a smartphone syncing time with an analog wristwatch via a wireless connection.

    Easy to operate via smartphone

  • Minimalist black and white icon of a dual-time wristwatch with a main dial and a smaller sub-dial.

    Check dual city time at a glance

Shop G-SHOCK MASTER OF G EMERGENCY COLOURS
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