Casio G-Shock G-Steel Carbon Core - GSTB300-1A

A model that adds a rugged design to a G-STEEL model that uses the carbon
 core guard structure from G-SHOCK, which continues to evolve in the pursuit
 of toughness. 

A model covered with a rugged and playful design typical of G-SHOCK,
with a disc dial that shows the current function mode and remaining
charge at the 6 o'clock position, and ruggedly designed front button. 

Additionally, the round digital graphic at the 1 to 2 o'clock position, 
which is asymmetrical with the disc dial, achieves both functionality 
and design, together with the digital LCD at the 12 o'clock position. 

A model that uses a ruggedly designed resin band in pursuit of functional 
beauty.

Case size: 51 × 50.3 × 15.3 mm
Weight: 82 g
Case and bezel material: Resin / Stainless steel
Band: Resin Band
Construction: Shock Resistant
Carbon Core Guard structure
Water resistance: 200 meters 
Power supply / battery life: Tough Solar / Solar powered

Wireless linking using Bluetooth®
Smartphone Link feature: Mobile link
Apps: CASIO WATCHES

Glass: Mineral Glass
Other: Neobrite

Watch Features 

World time
39 time zones* (39 cities + coordinated universal time), 
daylight saving on/off, 
auto summer time (DST) switching, Home city/World time 
city swapping
*May be updated when connected to a smartphone.

Stopwatch
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

Timer
Countdown timer
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 & 1-hour increments)

Alarm / hourly time signal
Hourly time signal
5 multi-function alarms (with daily, 1 time, schedule)

Light
Double LED light
LED light for the face (Full auto LED light, Super illuminator, 
selectable illumination duration (1.5 seconds or 3 seconds), 
afterglow
LED backlight for the digital display (Full auto LED light, 
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 and hands stop
to save power when the watch is left in the dark)

Battery display/alert
Battery level indicator

Run time
Approx. battery operating time:
6 months on rechargeable battery (operation period with normal 
use without exposure to light after charge)
19 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
Hand shift feature (Hands move out of the way to provide an unobstructed 
view of digital display contents.)
Regular timekeeping:
Analog: 3 hands hour, minute (hand moves every 10 seconds), second
Digital: Hour, minute, second, pm, month, date, day