• LED light (LCD part only)
  Selectable illumination duration, afterglow
• Solar powered
• World time
  31 time zones (48 cities + coordinated universal time), city code display, daylight saving on/off, Home city/World time city swapping
• 1/100-second stopwatch
  Measuring capacity: 59'59.99''
  Measuring modes: Elapsed time, split time
• 2 countdown timers
  Can be used during interval training that alternates between two different paces.
  Measuring unit: 1 second
  Input range: 00'05" to 99'55" (1-minute increments and 5-second increments)
  Other: Number of repeats settable from 1 to 10
• 5 daily alarms
• Hourly time signal
• Battery power 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
• Regular timekeeping: Hour, minute, second, pm, month, day, 6-language day of the week indicator (English, Portuguese, Spanish, French, German, Italian)
• Accuracy: ±30 seconds per month
• Approx. battery operating time:
  10 months on rechargeable battery (operation period with normal use without exposure to light after charge)
  23 months on rechargeable battery (operation period when stored in total darkness with the power save function on after full charge)

- See more at: http://www.tsotime.com/casio/40-casio-solar-powered-aq-s800wd-7ev-aq-s800wd.html