From G-SHOCK, the watch brand that is constantly setting new standards for timekeeping toughness, comes new bi-colour molded models with a sporty mix design theme. With these new models, basic Black brand colouring is highLighted by striking colours that are often used for high-tech sneakers and other fashion motifs. Yellow resin is molded onto the inside of the band and each mode also uses yellow for other components. These models also use orange gradations that are similar to those often seen on various types of sportswear. The GA-400BY has a colourful semi-transparent ring inside its bezel, while the GA-100BY has a gradations pattern on its face. The result of all of this is strikingly colourful designs that are sporty and attractive.

• LED Light 
  Auto Light switch, selectable illumination duration, afterglow
• World time 
  29 time zones (48 cities + coordinated universal time), dayLight saving on/off, Home city / World time city swapping
• 1/1000-second stopwatch 
  Measuring capacity: 99:59'59.999'' 
  Measuring modes: Elapsed time, lap time, split time 
  Others: Speed (0 to 1998 units / hour), Distance input (0.0 to 99.9) 
  Mach indicator (speed exceeding 1225 units / hour)
• 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) 
  Other: Auto-repeat
• 5 daily alarms (with 1 snooze alarm)
• Hourly time signal
• Full auto-calendar (to year 2099)
• 12/24-hour format
• Regular timekeeping 
  Analog: 2 hands (hour, minute (hand moves every 20 seconds)), 1 dial (speed) 
  Digital: Hour, minute, second, pm, month, date, day
• Accuracy: ±15 seconds per month
• Approx. battery life: 2 years on CR1220
• Size of case : 55 X 51.2 X 16.9 mm
• Total weight : 70 g
• LED:Amber