100% authentic, brand new, unused, original box, manual, black certificate of authenticity card included! This would make a perfect addition to your collection or a gift for a fellow G-SHOCK fan.



Welcome in the Year of the Snake with a special edition G-STEEL crafted at the intersection of metal and resin. Celebrate 2025 with innovative form and design inspired by the ancient ouroboros. This slim GSTB400 features an ouroboros motif, the ancient auspicious symbol of a serpent eating its own tail, representing infinity and immortality. This special timepiece pairs a silver-colored metal bezel and black watch face with gold-colored accents for a design that takes you smoothly from casual settings to formal occasions and back again. The side buttons and strip across the face from the 3 o’clock to 9 o’clock position add textural appeal with a snake pattern touch that nods to the Year of the Snake. The case back is engraved with a special ouroboros illustration representing infinite possibility. The GSTB400 brings together smaller components and a thinner module to deliver an even slimmer profile, while still offering the Bluetooth connectivity and solar power charging you want for greater convenience and significantly less power consumption. Add to this the watch’s Carbon Core Guard structure, and you have the slimmest G-STEEL yet (as of December 2024), measuring just 12.9 mm from case back to bezel top, over a millimeter slimmer than the GSTB100. Passionate attention to the smallest details — with large, easy-to-press stainless steel buttons, a resin band, and silver metal case featuring different finishes on the top and middle bezels — achieves an elegant, transformative look worthy of the Year of the Snake



SPECIFICATIONS:


Basic Information



Case size (L× W× H)

46.6 × 49.6 × 12.9 mm


Weight

86 g


Case and bezel material

Carbon / Stainless steel


Band

Resin


Construction

Shock Resistant

Carbon Core Guard structure


Water resistance

200-meter water resistance


Power supply and battery life


Tough Solar (Solar powered)


Smartphone Link/App Connectivity


Features

Smartphone Link feature

Mobile link (Wireless linking using Bluetooth®)


Apps

CASIO WATCHES


App connectivity feature


Auto time adjustment


Easy watch setting


Approximately 300 world time cities


Time & place


Reminder


Phone finder


Exterior Glass

Mineral Glass


Compatible band size

145 to 215 mm


Other

Neobrite


Watch Features

World time

38 time zones (38 cities + coordinated universal time), city code display, city name display, daylight saving on/off, auto summer time (DST) switching, Home city/World time city swapping


Stopwatch

1/100-second stopwatch


Measuring capacity:

00'00''00~59'59''99 (for the first 60 minutes)


1:00'00~23:59'59 (after 60 minutes)


Measuring unit:

1/100 second (for the first 60 minutes)

1 second (after 60 minutes)


Measuring modes:

Elapsed time, lap/split time


Timer


Countdown timer


Measuring unit: 1 second


Countdown range: 60 minutes


Countdown start time setting range: 1 second to 60 minutes (1-second increments and 1-minute increments)


Alarm/hourly time signal


5 daily alarms


Hourly time signal


Light

Double LED light


LED light for the face (Super illuminator, selectable illumination duration (1.5 seconds or 3 seconds), afterglow)


LED backlight for the digital display (Super illuminator, selectable illumination duration (1.5 seconds or 3 seconds), afterglow)


Light color

LED:White


Calendar

Full auto-calendar (to year 2099)


Mute feature


Button operation tone on/off


Energy saving feature


Power Saving (display goes blank to save power when the watch is left in the dark)


Battery display/alert


Battery level indicator


Run time

Approx. battery operating time:

7 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)


Accuracy

Accuracy: ±15 seconds per month (with no mobile link function)


Other features


12/24-hour format


Date/month display swapping


Day display (days of the week selectable in six languages)


Hand shift feature (Hands move out of the way to provide an unobstructed view of digital display contents.)


Regular timekeeping:

Analog: 2 hands (hour, minute (hand moves every 20 seconds), 1 dial (battery level, mode)


Digital: Hour, minute, second, pm, month, date, day