how to clean a g shock watch

*GST-B400MV-5A – Updated October 2021 color!

Size	★★★★★
Weight	★★★★★
Functions	★★★★★
Materials	★★★★★
Battery Years	★★★★★
Price	★★

How did we compose this rating? Enjoy our calculations →

*As an Amazon Associate, we may earn a small commission from qualifying purchases. Note, we do not spoil the site with hundreds of Ads. We want it to be clean and useful. By buying through our links to Amazon, you are investing in our development. We are trying to keep all links up to date and change them if needed.

Quick Content Guide

Japanese approaches to Tough and Functional Watches in GST-B400! *the most distinctive features in details
General information about the watch *year of first release, model range etc.
G-Shock GST-B400 Display Guide*for key functions only
GST-B400 Usage Patterns *what the watch is usually meant for
Feedback from Users and Experts *anonymous from different sources
GST-B400 Model Range *in different colors and bands
GST-B400 Limited Editions *unique style, materials, and price
The most distinctive specs *from our Editorial point of view
Other G-Shock GST Watches *similar by price and functions but different by cases
Official GST-B400 Video *only from Casio Company
Official GST-B400 Specs *all details and for base version GST-B400-1A
GST-B400 Comparison Table *with similar G-Shock Watches

Enjoy Japanese approaches to Tough and Functional Watches!

Tough Solar & Improved Readability. The GST-B400 is powered by G-SHOCK Tough Solar power system, charged by both real and artificial light sources. To ensure great readability, as well, a dial indicator at the 9 o'clock position display the mode, battery level and more.

Stylish & Sophisticated looks. The watch features a stainless-steel bezel in a sophisticated new shape. Attention to detail and material quality are paramount for the G-STEEL, featuring unique finishing techniques like hairline, mirror and polishing, highlighting an impressive array of surface textures that captivate the eye from every angle.

Metal Band with Double Slide Lever. This allows quick and easy change of the bands.

Slimness & Energy-Saving Module. Optimised, high-density mounting of the circuit board structure has made it possible to slim the module of the new GST-B400. A substantial reduction in power consumption was also achieved by reducing the number of watch hands to two and adopting a low-power Bluetooth® system.

Shock Resistant. Shock-resistant construction protects against impact and vibration.

G-SHOCK CONNECTED App. Connection with a phone requires installation of the G-SHOCK CONNECTED App on the phone.

Return to the Content Guide ↑

General Information

Price	320$ *average Amazon Price, we may earn commission from purchases
Year of first Release	2021
Suitable for Wrist Size	160 – 230 mm
Module Number	5657 / Manual
Model Range	G-STEEL (G-Steel are refined watches and combine high-quality materials with G-Shock's standard of toughness. Its layered guard structure boasts a double-layer bezel construction of stainless steel and resin or resin and fine resin which delivers the hard, sleek beauty of metal while retaining the impact absorption of resin.)
Battery Type	Solar (G-Shock Batteries)
Other Divisions the GST-B400 belongs to: *you may find all watches of the division by clicking on the link	G-Shock Ana-Digi G-Shock Bluetooth G-Shock Solar G-Shock 2021

Return to the Content Guide ↑

G-Shock GST-B400 Display Guide *for key functions only. For you to know how it works))

General Display

Hour hand
Minute hand
LCD
Mode hand
Indicates the current mode. In the Timekeeping Mode, this hand shows the current charge level.

Shifting Hands to Read the Digital Display

Hand shift moves the hands out of the way for easy viewing of display information

Phone Finder

You can use phone finder to trigger a tone on the phone to make it easy to find. The tone is forced to sound even if the phone is in vibrate mode.

Checking World Time

Enter the World Time.
After the currently selected World Time City name appears, the watch will display the current time in that city.

Return to the Content Guide ↑

GST-B400 Usage Patterns *what the watch is usually meant for

Return to the Content Guide ↑

Feedback from Users *accumulated information from our own comments and emails, forum threads, socials, reviews, etc.

PROs
+ looks a lot more expensive than it is
+ the strap looks very comfortable
+ fits just fine and the lightweight is a plus
+ they fixed the battery indicator from the gst-b100 so it's easier to check the battery level
+ they slimmed down the watch

CONs
– too few color/ stainless steel variants with straps without negative displays
– no backlight movement detector and timer
– no lume
– at that price it should DEFINITELY have a sapphire glass
– they removed a very useful second hand

Return to the Content Guide ↑

GST-B400 Model Range *may be updated

*You may find updated information about colors on our G-Shock 2021 New Releases page →

Return to the Content Guide ↑

GST-B400 Limited Editions *unique style, materials, and price

The Listing of All G-Shock GST-B400 Limited Watches → *with detailed description about the style

Return to the Content Guide ↑

The most distinctive specs of GST-B400 — Thin 12.9 mm case & Carbon Core Guard
*Editorial
— The Slimmest-Ever G-STEEL as for 2021 (it features a new, improved module built to deliver slimness)
— Beautiful battery level indicator at 9 o'clock (displays the mode, battery level and more)
— Vapor deposition-treated dials (for highly chromogenic and distinctive coloration)
— Tough Solar (CASIO's original solar-charging system converts not only sunlight but also light from fluorescent lamps and other sources into power)
— G-SHOCK Connected App (you may manage all watch settings through your phone)

Return to the Content Guide ↑

Other G-Shock GST Watches *similar by price and functions but different by cases

These are not all G-Shock GST Series. Here is a list of All G-Shock GST Watches →

Return to the Content Guide ↑

Official GST-B400 Video

Return to the Content Guide ↑

Official Marketing Focus from Casio

Introducing new color variations to the lineup of slim G-STEEL GST-B400 models with new, improved designs made possible by a thin module and carbon core guard structure. There is a standard model in this lineup, the GST-B400 with silver color face and resin band.
The GST-B400 is made possible by even further miniaturization of its parts and thinning of its modules without sacrificing any Bluetooth or solar function. Power consumption has also been significantly reduced.

Official GST-B400 Specs / Features *for base version GST-B400-1A

Case / bezel material: Resin / Stainless steel
Resin Band
Mineral Glass
Neobrite
Shock Resistant
Carbon Core Guard structure
200-meter water resistance
Shock resistant (G-SHOCK)
Tough Solar (Solar powered)
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)
Mobile link (Wireless linking using Bluetooth®）
Hand shift feature (Hands move out of the way to provide an unobstructed view of digital display contents)
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
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
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)
5 daily alarms
Hourly time signal
Battery level indicator
Power Saving (display goes blank to save power when the watch is left in the dark)
Full auto-calendar (to year 2099)
12/24-hour format
Button operation tone on/off
Date/month display swapping
Day display (days of the week selectable in six languages)
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
Accuracy: ±15 seconds per month (with no mobile link function)
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)
Size of case : 46.6×49.6×12.9mm
Total weight : 80g

Return to the Content Guide ↑

GST-B400 Comparison Table with similar G-Shock Watches

	GST-B400	GST-B300	GST-B200
Price (Amazon)	320$	300$	270$
Year of first Release	2021	2020	2019
Accuracy	Bluetooth (via phone app)	Bluetooth (via phone app)	Bluetooth (via phone app)
SmartWatch Features	G-SHOCK Connected App	G-SHOCK Connected App	G-SHOCK Connected App
Light	Neobrite and Double LED light	Neobrite and Double LED light (Full auto LED light, Super illuminator)	Neobrite and Double LED light (Full auto LED light, Super illuminator)
Alarm	5 daily alarms	5 multi-function alarms (with daily, 1 time, schedule)	5 multi-function alarms (with daily, 1 time, schedule)
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)	Measuring unit: 1/10 second Countdown range: 24 hours Countdown start time setting range: 1 second to 24 hours (1-second increments, 1-minute increments and 1-hour increments)	Measuring unit: 1/10 second Countdown range: 24 hours Countdown start time setting range: 1 second to 24 hours (1-second increments, 1-minute increments and 1-hour increments)
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	1/1000-second stopwatch Measuring capacity: 00'00''000~59'59''999 (for the first 60 minutes) 1:00'00''0~23:59'59''9 (after 60 minutes) Measuring unit: 1/1000 second (for the first 60 minutes) 1/10 second (after 60 minutes) Measuring modes: Elapsed time, split time	1/1000-second stopwatch Measuring capacity: 00'00''000~59'59''999 (for the first 60 minutes) 1:00'00''0~23:59'59''9 (after 60 minutes) Measuring unit: 1/1000 second (for the first 60 minutes) 1/10 second (after 60 minutes) Measuring modes: Elapsed time, split time
Hourly Time Signal	Yes	Yes	Yes
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	39 time zones* (39 cities + coordinated universal time), daylight saving on/off, auto summer time (DST) switching, Home city/World time city swapping	39 time zones* (39 cities + coordinated universal time), daylight saving on/off, auto summer time (DST) switching, Home city/World time city swapping
Multi Day Format	Yes	Yes	No
Multi Language Day	Yes	Yes	No
Second Hand	No	Yes	Yes
Case / bezel material	Resin / Stainless steel	Resin / Stainless steel	Carbon / Stainless steel
Glass	Mineral Glass	Mineral Glass	Mineral Glass
Battery	Solar powered	Solar powered CTL1616	Solar powered CTL1616
Size (mm) *we consider 48.9×42.8×13.4 to be a traditional watch size (as in DW-5600). So you are to compare how far or close the watch is to this size	46.6×49.6×12.9	51×50×15.5	53.3×49.2×14.5